POWER TRAIN ELECTRONIC CONTROL SYSTEM Caterpillar


Testing And Adjusting

Usage:

General Troubleshooting Information

The diagnostics for the ECM system are accessed through Vital Information Management System (VIMS) and Caterpillar Electronic Technician (ET) service tool. Troubleshooting the power train system requires additional information from the machine Service Manual. The service manual SENR6059 "Vital Information Management System (VIMS)", the Electrical System Schematic, the Parts Manual and the Operation & Maintenance Manual are required support material.

As a guide, a simplified system schematic is included at the end of this manual. For an accurate representation of the machine being diagnosed, see the Electrical System Schematic in the machine Service Manual.

When the troubleshooting procedure instructs to REPAIR THE HARNESS, always use the Electrical System Schematic in the machine Service Manual to trace the circuit. Perform continuity checks at connectors to locate harness failures. At component connectors, always check the ground circuit. For ECM power circuits less than 2 ohms of resistance is required between the connector ground contacts and frame ground. For signal circuits (sensors, switches, solenoids etc.) less than 5 ohms of resistance is required for normal operation. Resistance greater than 5 ohms can cause incorrect diagnosing of problems.

During troubleshooting, inspect all component and harness connections before any component is replaced. If these connections are not clean and tight they can cause electrical problems, either permanent or intermittent (come and go). Check that the wires are pushed into the connectors completely. Make sure the connections are tight before other tests are made.

If wire insulation is punctured during troubleshooting, repair after probing. Seal the punctures with 8T-0065 Adhesive. Cover the adhesive with two layers of 1P-0810 Tape.

Failure of an electrical component can cause, or be caused by the failure of one or more other components. Always attempt to find and correct the cause of electrical system failure before replacing a component.

Service Tools

The following service tools should be used to aid in troubleshooting the electrical system.

Caterpillar Electronic Technician (ET)6V-7070 or 9U-7330 Digital Multimeter or equivalent.8T-3224 Needle Tip Group7X-1710 Cable Probe Group8T-8726 Adapter Cable4C-3406 Connector Repair Kit - Deutsch

For more information on ET, see the topic Using ET To Determine Service Codes under the topic Troubleshooting Faults With Service Codes.

Use the digital multimeter for making continuity (resistance) checks or voltage measurements. For instruction on use of the 6V-7070, see Special Instruction SEHS7734. The 7X-1710 Cable Probe Group is used to make measurements at connectors without disconnecting them. The probes are pushed in the back of the connector alongside the wire. The 8T-8726 Adapter Cable is a 3 pin breakout cable used to make measurements in sensor circuits.

NOTE: Use of continuity testers (such as 8T-0500), or voltage testers (such as 5P-7277) are not recommended for use on present-day Caterpillar electrical circuits, except for harness tests.

Electrical Component And Connector Locations

Remove cover to gain access to the power train, VIMS main and interface modules located behind the cab.


Component Location
(1) VIMS interface module #2. (2) VIMS interface module #1. (3) VIMS main module. (4) Power train ECM.


Component Location
(5) Diagnostic service tool connector (for ET).

The diagnostic service tool connector (ET) is located in the cab next to the parking brake knob.

The Electrical System Schematic, Parts Manual and the Operation & Maintenance Manual for the machine being serviced, should all be used to locate electrical components and connectors.

The following is a guide to reading the Harness Connector and Component Location charts, the machine profile and the area views all found on the backside of the Electrical System Schematic module.

* Component Location Chart:

The component location chart uses white circles as location labels in the machine profile and area views. Alphabetical letters in the machine location column indicate a general area of the machine. See the corresponding footnote at the end of the chart for a description of the location.

* Harness Connector Location Chart:

The harness connector location chart uses white circles as location labels in the general and area views.

Connector Contact Numbers

Power Train ECM


Power Train ECM
(1) Connector J1. (2) Connector J2.


Power Train ECM Connector
(3) Screw.

To remove the machine harness from the ECM, use screw (3) in the center of the harness connector.

Connector Inspection

Intermittent electrical problems are often caused by poor connections. Use the following checks as a guide for inspecting connectors.

* Check connector mating.

Ensure locking rings lock into place.

Ensure that the screw in the center of the connector is tight.

Ensure that the connector pins and sockets align properly.

* Check wires at the connector.

Ensure that the wires enter the back of the connector straight not at an angle.

Ensure that each wire is properly crimped into the proper connector contact.

Ensure that each connector contact is properly locked into the connector body. When locked properly, the contact (or wire) cannot be pulled out of the connector body without excessive force.

* Check each wire for nicks or signs of abrasion in the insulation.
* Check for moisture at the connector. Possible sources are:

Damaged or lost connector seals.

Missing or loose wire hole plugs.

Wires not entering the back of the connector straight. If wires enter at an angle, there may not be a good seal between the connector and the wire insulation.

From other connectors with poor seals by traveling inside the wire insulation.

* Check for dirty or corroded contacts.

Clean contacts with a cotton swab or a soft brush and denatured alcohol only.

* Check each pin and socket.

Use a new pin and socket and check each contact of the connector for a snug fit. The new contact should stay connected if the connector is held with the contacts facing down.

Troubleshooting Faults With Service Codes

Use VIMS, or ET to determine the ECM system service codes. After determining the service codes, go to the procedure, under the subject Procedures that follows. Perform the procedure that corresponds to the service code (CID and FMI) determined. The following is a list of possible service codes for the ECM.

Using Caterpillar Electronic Technician (ET) To Determine Service Codes


ET Connections

(1) IBM compatible personal computer with Caterpillar Electronic Technician software installed (see note below).

(2) 139-4166 Data Link Cable or 7X-1570 Data Link Cable.

(3) 7X-1425 Cable and 4C-6805 Adapter.

(4) JEBD3003, JERD2124 and JERD2129 Caterpillar Electronic Technician software.

(5) 7X-1700 Communications Adapter (with NEXG4523 Communications Adapter Software installed).

NOTE: Caterpillar Electronic Technician is a software program that runs on an IBM compatible personal computer. To use Caterpillar Electronic Technician (ET), order JERD2124, ET Single Use Program License software; JEHP1026, the information and requirements sheet; 7X-1425, the RS232 connection cable, and JERD2142, the Data Subscription. The requirements and information sheet lists the hardware required and the features of ET.

The service tool ET is not needed to determine or clear service codes, but it makes the tasks easier and faster. ET can also display service code history information and parameter status information. These features make ET a useful troubleshooting tool.

ET connects to the machine service connector and communicates with the ECM's over the data link. The service connector is located next to the parking brake knob in the cab. For more information, see the topic Electrical Component And Connector Locations and the Electrical System Schematic in the machine Service Manual.

When connected to the machine, turn key start switch to "run" position and start ET. ET will initiate communications with the ECM's on the machine. After communication has been established, ET will list the ECM'S on the machine. Choose the menu item "Transmission 994D". After determining the service codes with ET, see the topic Troubleshooting Procedures, that follows, for troubleshooting procedures that correspond to the service codes.


ET Screen For Available ECM'S

ET Status Groups

ET has status groups to display parameter status information. The 994D Power Train status groups 1 through 6 are shown in the following illustrations.

NOTE: These examples are for ET version 2.3. Other versions may differ from these examples.


ET Screen For Selecting A Status Group


ET Screen For Transmission 994D Status Group 1


ET Screen For Transmission 994D Status Group 2


ET Screen For Transmission 994D Status Group 3


ET Screen For Transmission 994D Status Group 4


ET Screen For Transmission 994D Status Group 5


ET Screen For Transmission 994D Status Group 6

Using VIMS To Determine Service Codes


VIMS Message Center Module
(1) Alert indicator. (2) Data logging indicator. (3) Message area. (4) Universal gauge. (5) Gauge warning area.

Most all VIMS maintenance events are delayed eight seconds from the beginning of the event until it is displayed. Any maintenance event shown in the event list will include this eight seconds in the event duration. Maintenance events originating in ECMs other than VIMS are delayed within that ECM software. VIMS will then immediately show an event as soon as that event is shown in the ECM of origin.

ACTIVE maintenance events are shown in message area (3). A maintenance event is specified by showing that a parameter has an ERROR and instructions for the operator like CALL SHOP. If multiple ACTIVE maintenance events are present, each will be scrolled in the message area in three second intervals. The following is an example of the impeller solenoid pressure circuit having an error.

Pressing the <F1> key toggles the display to show (on line two) the MID, CID and FMI codes for the maintenance event. Example:

When in gauge mode, F1 will show the fault. F1 again will show the FMI code verbally like: Short to ground.

To troubleshoot a VIMS maintenance event, go to the procedure with the same CID and FMI within the topic Troubleshooting Procedures.

Troubleshooting Procedures

These procedures are only for service codes originating from the power train ECM. The service codes are viewed on VIMS or on Caterpillar Electronic Technician (ET). Go to the following procedure which corresponds to the CID and FMI which is being shown on the VIMS display or on Caterpillar ET. See the topic Troubleshooting System Events To Determine Service Codes or the topic Using Caterpillar Electronic Technician (ET) To Determine Service Codes.

The following procedures may cause new faults to be logged. Therefore, before performing any procedures, make a list of all service codes to determine system problems. At the completion of each procedure, clear the faults that were caused by the procedure.

NOTE: Before performing a procedure, always check all the fuses and circuit breakers. Find and repair the cause of any blown fuse or tripped circuit breaker. Replace any blown fuses and reset any tripped circuit breakers before beginning to troubleshoot.

Module Identification (MID)

Maintenance events from electronic control modules other than VIMS modules are shown on the VIMS message center. Other electronic control modules transfer this diagnostic information by way of the CAT data link to the VIMS main module.

The Module Identifier (MID) code identifies which electronic control module detected the fault. Each electronic control module on the machine has a unique MID code. Use the following chart to match the MID code for each fault, to an electronic control module. If the MID code is not shown in the following chart, see the Module Identifier (MID) chart on the Electrical System Schematic for the machine being serviced. After determining which electronic control module detected the fault, see the service manual module for that ECM for troubleshooting information (CID/FMI). The service manual modules for each ECM are part of the machine Service Manual.

If the MID code is for the power train module use this service manual module (RENR2522) to troubleshoot the fault. This service manual module (RENR2522) contains troubleshooting procedures for the power train electronic control modules only. To troubleshoot a power train module fault, go to the procedure with the same CID and FMI.

Failure Mode Identifier

Failure Mode Identifier (FMI) codes are defined by SAE standards. The definitions listed are those of Caterpillar as it applies to our product. The following diagram will help understand FMI use with sensors like frequency (Transmission Speed), analog (Impeller Clutch Pressure) and digital (PWM).

Detailed FMI Explanation

FMI 00 - Data Valid But Above Normal Operating Range. Every electronic control system sets a high limit for the "expected" operating range of the signal. The limit includes "over range" signals such as high torque converter temperatures. A sensor that is still working but sending a signal above the expected limit will cause an FMI 00 to be stored.

Some possible causes of FMI 00 can be:

* Signal above normal (High pressure/temperature)
* Switch shorted to +voltage
* Calibration needed (FMI 03 preferred)

Example - A certain PWM sensor is expected to generate a valid signal over 80 percent duty cycle. If the sensor generates an 81 percent duty cycle signal, it is still working but it is above the expected signal limits.

FMI 01 - Data Valid But Below Normal Operating Range. Every electronic control system sets a low limit for the "expected" operating range of the signal. The limit includes "under range" signals such as a low engine oil pressure signal from a working sensor. A sensor that is still working but sending a signal below the expected limit will cause an FMI 01 to be stored.

Some possible causes of FMI 01 can be:

* Signal below normal (Low voltage/pressure/temperature)
* Retarded timing

Example - A certain PWM sensor is not expected to generate a PWM signal below 5 percent even with zero air pressure. If it generates a 4 percent duty cycle with the engine shutdown, it is still working but is below the expected signal limits.

FMI 02 - Data Erratic, Intermittent Or Incorrect. Signal data from a component is present. Then the signal is either gone, unstable or invalid as recognized by the control doing diagnostics. Data can be correct sometimes and not at other times. Also this condition relates to communication between controls, an example would be when VIMS is looking for engine speed from the electronic engine control over the Cat data link.

Some possible causes of FMI 02 can be:

* Faulty connections in switches, harness etc.
* Intermittent/erratic signal
* Programed data changed
* Noisy signal
* Signal out of range (FMI 00 or 01 preferred)

FMI 03 - Voltage Above Normal Or Shorted High. The voltage identified is higher than expected from the component or system (like sensor power) that the CID identifies. FMI 03 most often relates to a signal circuit.

The responsible elements of the system that could be the root cause include:

* The sensor (switch)
* The harness
* The related electronic control

Some possible causes of FMI 03 can be:

* A sensor that does not generate an alternating signal (duty cycle) and the output stops (fails) "high" or at maximum output.
* A harness with the sensor signal wire shorted to the sensor power supply or shorted to any voltage greater than the sensor power supply voltage.
* An open sensor signal wire between the sensor and the control. Electronic controls normally "pull" the input circuit to a positive voltage level (often 5.0 DCV) when the sensor is disconnected.
* A faulty control where the connector contact of the sensor signal is internally shorted to a positive source or a faulty control (very unlikely) that believes a failure exists when the circuit is actually working correctly.

FMI 04 - Voltage Below Normal Or Shorted Low. Reference FMI 03 except voltage is lower than expected. Very similar to FMI 06 and is sometimes used instead of FMI 06.

The responsible elements of the system that could be the root cause include:

* The sensor
* The harness
* The related electronic control

Some possible cause of FMI 04 can be:

* A sensor that does not generate an alternating signal (duty cycle) and the output stops (fails) "low" or at minimum output.
* Harness signal wire is shorted to ground.
* Electronic control has internal short to ground on the connector contact of the signal input.

FMI 05 - Current Below Normal Or Open Circuit. The control detects that the current in the monitored circuit described by the CID is less than expected and usually results from an open circuit. Most often FMI 05 is related to a control output driver circuit.

Some possible causes of FMI 05 can be:

* Open circuit or poor harness connection
* High resistance circuit in component (relay coil)
* Component in open position (switch)

FMI 06 - Current Above Normal Or Grounded Circuit. The same as FMI 05 except current is higher than expected. For example, when a circuit is shorted to ground. Very similar to FMI 04 and sometimes used instead of FMI 04.

Some possible causes of FMI 06 can be:

* Short to ground in harness
* Low resistance (failure) in component coil (relay)
* Electronic control has internal short to ground on the connector contact of signal input.

FMI 07 - Mechanical System Not Responding Properly. When an electronic control sends an electrical command or output to a mechanical system and the result is not as expected.

Example - Slow shift ICM transmission (EPTCII) caused by a sluggish solenoid valve.

Some possible causes of FMI 07 can be:

* Component improper response
* Component stuck in position
* Component failure
* Engine is shutdown
* Improper machine operation

FMI 08 - Abnormal Frequency, Pulse Width Or Period. When the signal frequency, or width of a given signal pulse, is not in the expected range. Can also relate to a faulty or open sensor output circuit.

NOTE: Period is the time in seconds for one cycle at a given frequency or repetition rate.

Some possible causes of FMI 08 can be:

* Intermittent or poor signal circuit connections
* Misfire
* Noisy signal caused from nearby radio or magnetic fields
* Loose mechanical devices (gears)

FMI 09 - Abnormal Update. Relates to communication between electronic controls on a data link. FMI 09 occurs when a given control is not able to get information from another when the data is required or expected.

Some possible causes of FMI 09 can be:

* Module not communicating on the data link as expected
* Abnormal update data rate
* No communication on the data link at all
* Electronic control failure
* Mismatch of software between electronic controls

FMI 10 - Abnormal Rate Of Change. Relates to signal that changes at a rate faster/slower than expected. The RATE OF CHANGE, is outside of the expected limits. This value is not outside of the expected maximum or minimum value.

Example - When the signal from a transmission output speed sensor (ground speed) indicates that the machine is accelerating (or decelerating) faster than could possibly occur during actual operation.

FMI 11 - Failure Mode Not Identifiable. Relates to a signal where the electronic control identifies more than one FMI as responsible for a single failure.

Some possible causes of FMI 11 can be:

* Mechanical failure
* Machine damage to multiple circuits

FMI 12 - Bad Device Or Component. Describes a condition where an electronic control sends a signal to another electronic module over a data link and expects a response but gets no response or the response is incorrect. This condition also applies where a module is expected to send data periodically and does not. Could also relate to a data link failure (CID 0248 would also be displayed) or to control self diagnostics where the control believes it is defective. This could result from a software mismatch (wrong change level) between controls.

Some possible causes of FMI 12 can be:

* Control Failure
* Data link failure
* One or more controls with the incorrect software

FMI 13 - Out Of Calibration. For a given mechanical condition, the electrical signal is not within the limits the electronic control expects. The sensor needs calibration, adjustment or replacement.

The possible causes of FMI 13 can be:

* Calibration Required
* Data out of range

FMI 14, 15 and 20 - Not Used.

FMI 16 - Parameter Not Available. The electronic control providing data does not support the requested parameter so it is "not available". Indicates possible software mismatch between electronic controls.

FMI 17 - Module Not Responding. Parameter error due to the source module (module where the data is expected to originate) not responding to data request. Source module or wire harness is faulty.

FMI 18 - Sensor Supply Failure. Parameter error due to a failed power supply in the module supplying this voltage.

FMI 19 - Condition Not Met. Conditions defined in the software were not met to store trend data.

CID 0041 Procedure - +8V Sensor Supply

FMI 03


Sensor Power Supply Voltage Schematic

The sensor supply is a power supply that is internal to the ECM. The sensor supply provides +8 and +10 DCV to operate the sensors. The sensors that use +8 DCV are the torque converter oil temperature sensor and the impeller clutch pressure sensor. The sensors that use +10 DCV are the torque converter output speed sensor and the transmission output speed sensor.

This fault is recorded when the ECM reads the voltage of the sensor supply circuit as above normal range.

The possible causes of this fault are:

+8V sensor supply circuit (wire C985-BU) to the sensor is shorted to +battery.

+10V sensor supply circuit (wire 709-OR) to the sensor is shorted to +battery.

Faulty sensor.

ECM is faulty (unlikely).

Service Note: Ensure that the CID 0041 FMI 03 is active.

NOTE: Refer to the sensor power supply voltage schematic for the sensor being tested.

STEP 1. Check Sensor.

a. Turn the key start switch and the disconnect switch to the OFF position.

b. Disconnect the machine harness from the sensor.

c. Turn the key start switch and disconnect switch to the ON position.

d. Measure the voltage at the machine harness connector for the sensor pin A to frame ground.

EXPECTED RESULT: The voltage should be +8V ± 0.5V for the torque converter oil temperature sensor and the impeller clutch pressure sensor. The voltage should be +10V ± 0.5V for the torque converter output speed sensor and the transmission output speed sensor.

RESULTS:

* OK - Proceed to next step.
* NOT OK - There is a problem in the sensor supply circuit in the machine harness. Proceed to Step 3.

STEP 2. Check Sensor Harness.

a. Turn the key start switch and the disconnect switch to the OFF position.

b. Reconnect the machine harness to the sensor.

c. Turn the key start switch and disconnect switch to the ON position.

EXPECTED RESULT: The fault is still active.

RESULTS:

* YES - Fault is still active. Could be failed sensor. Replace sensor and repeat Step 2.
* NO - Fault is no longer active. There may have been an intermittent in the machine harness connection. Proceed to Step 8.

STEP 3. Check ECM.

a. Turn the key start switch and the disconnect switch to the OFF position.

b. With sensor machine harness disconnected, disconnect the machine harness J1 and J2 from the ECM.

c. Turn the key start switch and disconnect switch to the ON position.

d. For a +8V sensor measure the voltage at the machine harness J2-12 (sensor supply) to frame ground. For a +10V sensor measure the voltage at the machine harness J2-9 (sensor supply) to frame ground.

EXPECTED RESULT: The voltage should be 0 ± 0.5 DCV.

RESULTS:

* OK - There may be a short in the harness that is powered by the ECM. Proceed to next step.
* NOT OK - There is a short in the machine harness that is not powered by the power train ECM. Repair or replace harness. STOP.

STEP 4. Check If Fault Remains.

a. Turn the key start switch and the disconnect switch to the OFF position.

b. Reconnect the machine harness J1 and J2 to the ECM.

c. Turn the key start switch and disconnect switch to the ON position.

EXPECTED RESULT: Is fault still active?

RESULTS:

* YES - Fault is still active. Proceed to next step.
* NO - Fault is no longer active. There may have been an intermittent in the machine harness connection. Proceed to Step 8.

STEP 5. Check +8V Or +10V Sensor Supply From ECM.

a. Make sure key start and disconnect switch are in the ON position.

b. Use 7X-1710 Cable Probe to measure the voltage for a +8V sensor at the machine harness J2-12 (sensor supply) to 202-BK (ground). For a +10V sensor measure the voltage at the machine harness J2-9 (sensor supply) to G939-PK (sensor return).

EXPECTED RESULT: The voltage should be +8V ± 0.5V for the torque converter oil temperature sensor and the impeller clutch pressure sensor. The voltage should be +10V ± 0.5V for the torque converter output speed sensor and the transmission output speed sensor.

RESULTS:

* OK - There may be a fault internal to the ECM. Proceed to Step 7.
* NOT OK - There is a short in the machine harness that is powered by the power train ECM. Proceed to next step.

STEP 6. Isolate Short In Machine Harness.

a. Turn the key start and disconnect switch to the OFF position.

b. Use service tool 4C-3406 Connector Repair Kit to remove wire J2-12 (C985-BU) for the +8V sensor or remove wire J2-9 (C709-OR) for the +10V sensor from the connector.

c. Turn the key start and disconnect start switch to the ON position.

d. Measure the voltage from wire C985-BU to 202-BK for the +8V sensor. Measure the voltage from wire 709-OR to G939-BU for the +10V sensor.

EXPECTED RESULT: The voltage should be 0 ± 0.5 DCV.

RESULTS:

* OK - There may be a fault internal to the ECM. Proceed to next step.
* NOT OK - There is a short in the machine harness that is not powered by the power train ECM. Repair or replace harness. STOP.

STEP 7. Check If Fault Remains.

a. Turn the key start switch and the disconnect switch to the OFF position.

b. Make sure all machine harness wires are properly connected to the ECM.

c. Turn the key start switch and disconnect switch to the ON position.

EXPECTED RESULT: Is the fault still active?

RESULTS:

* YES - Fault is still active. There may be a fault internal to the ECM, replace the ECM. See the subject ECM Replacement. STOP.
* NO - Fault is no longer active. There may have been an intermittent in the machine harness connection. Proceed to Step 8.

STEP 8. Check Machine Status.

a. Make sure all components that were serviced are properly connected.

b. Clear all faults stored in the ECM.

c. Operate machine.

EXPECTED RESULT: Fault is no longer active.

RESULTS:

* OK - REPAIR COMPLETE. STOP.
* NOT OK - Fault is still active, recheck system.

FMI 04

The sensor supply is a power supply that is internal to the ECM. The sensor supply provides +8 and +10 DCV to operate the sensors. The sensors that use +8 DCV are the torque converter oil temperature sensor and the impeller clutch pressure sensor. The sensors that use +10 DCV are the torque converter output speed sensor and the transmission output speed sensor.

This fault is recorded when the ECM reads the voltage of the sensor supply circuit as too low (less than 7.5V for +8V sensor or less than 9.5V for +10V sensor).

The possible causes of this fault are:

+8V sensor supply circuit (wire C985-BU) to the sensor is shorted to ground.

+10V sensor supply circuit (wire 709-OR) to the sensor is shorted to ground.

Sensor is faulty.

ECM is faulty (unlikely).

Service Note: Ensure that the CID 0041 FMI 04 fault is still active.

STEP 1. Check Sensor.

a. Turn the key start switch to the ON position.

b. Access VIMS message center and ensure that CID 0041 FMI 04 is active.

c. While observing the status of the fault disconnect the machine harness from the sensor.

EXPECTED RESULT: If the sensor is not the cause of the fault, the fault remains active. If the sensor is faulty, the fault is no longer active.

RESULTS:

* OK - The sensor is not faulty. The machine harness or the ECM may be faulty. Proceed to next step.
* NOT OK - The machine harness and the ECM are operating properly. The sensor is faulty. Replace the sensor. STOP.

STEP 2. Check +8V Or +10V Sensor Supply Circuit For Short To Ground. The sensor remains disconnected from the machine harness.

a. Turn the key start and disconnect switch to the OFF position.

b. Disconnect the machine harness connectors J1 and J2 from the ECM.

c. At machine harness connector J2, measure the resistance from contact J2-12 (+8V) or J2-9 (+10V) to all possible sources of ground. The possible ground sources are: J1-2 (wire A273-BK), J1-5 (wire A273-BK), J1-7 (wire 975-WH), J1-15 (wire G939-PK), J1-16 (wire 202-BK), J2-3 (wire 975-WH) and frame ground.

EXPECTED RESULT: Each resistance should be greater than 5000 ohms.

RESULTS:

* OK - The machine harness is correct. Proceed to next step.
* NOT OK - There is a short in the machine harness. The short is between the +8V circuit (J2-12, wire C985-BU) and a ground source or the short is between the +10V circuit (J2-9, wire 709-OR) and a ground source. Repair or replace the machine harness. STOP.

STEP 3. Check If Fault Remains.

a. Clean the contacts of the harness connectors.

b. Reconnect all harness connectors.

c. Turn the key start and disconnect switch to the ON position.

d. Operate the machine.

e. Check to see if CID 0041 FMI 04 is active.

EXPECTED RESULT: CID 0041 FMI 04 fault still active.

RESULTS:

* YES - The fault has not been corrected. It is unlikely that the ECM is faulty. Perform the previous Steps again. If the cause of the fault is not found, replace the ECM. See the topic ECM Replacement. STOP.
* NO - Fault is NOT present; the fault does not exist at this time. The initial fault was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation. STOP.

CID 0138 Procedure - Reduced Rimpull Selector Switch


Reduced Rimpull Selector Switch Schematic

FMI 03

The reduced rimpull selector switch has four N/O inputs to the ECM. During normal operation, one of the inputs is grounded and the other three inputs are open. If all inputs are the same, the ECM detects a fault. This fault is detected when all inputs are either open or shorted to +battery. Before performing this procedure use the Switch Continuity chart to determine the connector and contact that corresponds to the faulty circuit.

Service Notes: Ensure that the desired fault CID FMI 03 is active.

NOTE: Step 1 can create other faults that the ECM detects. Ignore these created faults and clear them when this fault is corrected.

STEP 1. Check For Open Circuit.

a. Turn the disconnect switch and the key start switch to the OFF position.

b. Disconnect the machine harness from the ECM.

c. At the machine harness connector for the ECM, check the continuity to ground of the contacts with the switch activated in the four positions. See the Switch Continuity chart.

EXPECTED RESULT: Continuity check does not agree with the chart.

RESULTS:

* YES - Continuity check does NOT agree with chart; the harness or switch is faulty. Go to Step 2.
* NO - Continuity check agrees with chart; Go to Step 3.

STEP 2. Check Switch.

a. Disconnect the machine harness from the switch.

b. Check the continuity to ground of the contacts with the switch activated in the four positions. See the Switch Continuity Chart.

EXPECTED RESULT: Continuity check does not agree with the chart.

RESULTS:

* YES - Continuity check does not agree with the chart; switch is faulty. Repair or replace the switch.
* NO - Continuity check agrees with the chart; Repair or replace the machine harness. STOP.

STEP 3. Check For Short To +B.

At the machine harness connector for the ECM, check the continuity from each of the switch contact wires to contacts J1-1, 6, 40 and J2-12.

EXPECTED RESULT: Continuity exists between one of the sources of battery voltage and the switch circuit.

RESULTS:

* YES - Continuity exists between one of the sources of battery voltage. Machine harness is faulty. Repair or replace machine harness. STOP.
* NO - Continuity does not exist between one of the sources of battery voltage and the switch circuit. Machine harness is correct. It is unlikely that an ECM is faulty. Perform the previous steps again. If the cause is not found, replace the ECM. See the subject ECM Replacement. STOP.

FMI 04

This fault is recorded when the status of all the inputs of the switch are grounded.

Service Notes: Ensure that the desired fault CID/FMI 04 fault is active.

NOTE: Step 1 can create other faults that the ECM detects. Ignore these created faults and clear them when this fault is corrected.

STEP 1. Check Switch.

a. Ensure that the fault is active.

b. Observe the ON/OFF status of the fault.

c. Disconnect the connector of the switch from the machine harness.

EXPECTED RESULT: Active fault changes from 04 to 03.

RESULTS:

* OK - The switch or it's harness is failed. Repeat this Step (Step 1) to verify the switch failure. Repair or replace the switch and or it's harness.
* NOT OK - Fault present indicator remains ON; the switch is not the cause of this fault. Go to Step 2.

STEP 2. Check Harness Circuit This Step checks the continuity of the entire harness circuit that is faulty; including the switch which was previously checked in Step 1.

a. Turn the disconnect switch to OFF position.

b. Connect the switch of Step 1 to the machine harness.

c. Disconnect the machine harness from the ECM.

d. At the machine harness connector for the ECM, check the continuity to ground of the contacts with the switch activated in the four positions. See the Switch Continuity chart.

EXPECTED RESULT: Continuity check does not agree with the chart.

RESULTS:

* YES - Continuity check does NOT agree with chart; the harness circuit is faulty. There is a short to ground in the machine harness between the ECM and the switch. Repair or replace the machine harness.
* NO - Continuity check agrees with chart; harness circuit is correct. It is unlikely that an electronic control is faulty. Perform the previous Steps again. If the cause is not found, replace the ECM. See the subject ECM Replacement. STOP.

CID 0168 Procedure - Electrical System Voltage

FMI 00

This fault is recorded when the Electronic Control Module (ECM) detects that battery voltage is greater than 35 DCV.

The result of this condition is that ON/OFF solenoids may be damaged if the voltage remains high for an extended period of time.

The 6V-2150 starting/charging analyzer can be used to troubleshoot the system. Refer to Special Instruction SEHS7768 Using the 6V-2150 Starting/Charging Analyzer Group.

Check to see if a battery charger or welder is being used on the machine. If so, disconnect the charger or welder and recheck for the service code. If the service code is still active, check the charging system.

STEP 1. Check System Voltage At ECM.

Measure the system voltage at connector J1 between contact 1 and 6 and contact 2 and 5 (wire 202-BK). The engine must be running at high idle.

EXPECTED RESULT: The voltage is 18 to 35 DCV.

RESULTS:

* Proceed to Step 2.
* NOT OK - Repair or replace the harness. If conditions are not resolved, proceed to Step 2.

STEP 2. Check Alternator.

a. Start and run the engine at high idle for several minutes.

b. Measure alternator voltage output at the battery posts.

EXPECTED RESULT: The voltage should be 27 to 29 DCV.

RESULTS:

* OK - The battery could be faulty. Proceed to Step 3.
* NOT OK - Repair or replace the alternator. The voltage regulator is faulty. If conditions are not resolved, proceed to Step 3.

STEP 3. Check Battery Voltage.

a. Turn the key start switch to the OFF position.

b. Measure the battery voltage at the battery posts.

EXPECTED RESULT: The voltage should be 15 to 35 DCV.

RESULTS:

* OK - The power train ECM could be faulty. Before replacing the ECM, recheck the system, the ECM is usually not the cause of a fault. Proceed to Step 4.
* NOT OK - Replace the battery. If conditions are not resolved, proceed to Step 4.

STEP 4. Repair Or Replace The ECM.

The ECM could be faulty. Before replacing the ECM, recheck the system, the ECM is usually not the cause of a fault.

Control replacement must be done in a specific manner. Specific instructions should be followed. Refer to ECM Replacement.

EXPECTED RESULT: The original condition no longer exists.

RESULTS:

* REPAIR COMPLETE - STOP.
* NOT OK - The original condition still exist, recheck the system. STOP.

FMI 01

This fault is recorded when the Electronic Control Module (ECM) detects that battery voltage is less than 18 DCV.

The 6V-2150 starting/charging analyzer can be used to troubleshoot the system. Refer to Special Instruction SEHS7768 Using the 6V-2150 Starting/Charging Analyzer Group.

Check to see if a battery charger or welder is being used on the machine. If so, disconnect the charger or welder and recheck for the service code. If the service code is still active, check the charging system.

STEP 1. Check System Voltage At ECM.

Measure the system voltage at connector J1 between contact 1 and 6 and contact 2 and 5 (wire 202-BK). The engine must be running at high idle.

EXPECTED RESULT: The voltage is 18 to 35 DCV.

RESULTS:

* Proceed to Step 2.
* NOT OK - Repair or replace the harness. If conditions are not resolved, proceed to Step 2.

STEP 2. Check Alternator.

a. Start and run the engine at high idle for several minutes.

b. Measure alternator voltage output at the battery posts.

EXPECTED RESULT: The voltage should be 27 to 29 DCV.

RESULTS:

* OK - The battery could be faulty. Proceed to Step 3.
* NOT OK - Repair or replace the alternator. The voltage regulator is faulty. If conditions are not resolved, proceed to Step 3.

STEP 3. Check Battery Voltage.

a. Turn the key start switch to the OFF position.

b. Measure the battery voltage at the battery posts.

EXPECTED RESULT: The voltage should be 15 to 35 DCV.

RESULTS:

* OK - The power train ECM could be faulty. Before replacing the ECM, recheck the system, the ECM is usually not the cause of a fault. Proceed to Step 4.
* NOT OK - Replace the battery. If conditions are not resolved, proceed to Step 4.

STEP 4. Repair Or Replace The ECM.

The ECM could be faulty. Before replacing the ECM, recheck the system, the ECM is usually not the cause of a fault.

Control replacement must be done in a specific manner. Specific instructions should be followed. Refer to ECM Replacement.

EXPECTED RESULT: The original condition no longer exists.

RESULTS:

* REPAIR COMPLETE - STOP.
* NOT OK - The original condition still exist, recheck the system. STOP.

CID 0190 Procedure - Engine Speed Sensor

FMI 11

This fault indicates that the engine ECM has detected a engine speed sensor fault and should be serviced first.

CID 0191 Procedure - Transmission Output Speed Sensor


Transmission Output Speed Sensor Schematic

FMI 00 And FMI 01

This fault is recorded when the ECM reads the transmission speed signal (wire 710-GN) as too high (FMI 00) or too low (FMI 01). The transmission output speed sensor is a frequency type of sensor. The transmission speed signal wire (wire 710-GN) connects to connector J2 contact 35 of the ECM connector. This troubleshooting procedure is for either an FMI 00 or FMI 01 fault.

NOTE: If a +10V sensor supply fault is present (CID 0041), correct it prior to proceeding with this CID 0191 fault. For proper operation of the transmission output speed sensor, it must be receiving supply power of 10.0 ± 0.5 DCV from the ECM.

Service Notes: Ensure that the CID 0191 FMI 00 or CID 0191 FMI 01 fault is active. The CID 0191 faults remain present until the ECM reads a good speed signal. Therefore the engine must be started and a good signal received before the ECM declares the fault is not present. Service personal should check for active faults in all gears. If the fault remains active in all gears, this would indicate a speed sensor problem. If the fault is not active in all gears, the clutch solenoids for the suspect gear(s) should be checked for mechanical failure.

STEP 1. Check Supply Voltage - Disconnect Nothing. Troubleshoot "as is" before disconnecting any circuits.

a. At the sensor, identify contact A, wire 709-OR (+10V) contact B, wire G939-PK (ground) and contact C, wire 710-GN (signal).

b. Turn the disconnect switch and the key start switch to the ON position.

c. Using 7X-1710 Cable Probe and measure the voltage (DCV) between wire 709-OR (+V) and wire G939-PK (ground).

EXPECTED RESULT: The voltage measured is 10.0 ± 0.5 DCV;

RESULTS:

* OK - The sensor supply voltage is correct. Go to Step 2.
* NOT OK - Voltage is NOT 10.0 ± 0.5 DCV; there is a fault. Check for open harness between the sensor and the ECM. Also see the procedures for CID 0041 (sensor supply). STOP.

STEP 2. Check For Open Harness.

a. The disconnect and key start switches remain in the OFF position.

b. At the machine harness connector for the sensor place a jumper from contact C to contact B.

c. Disconnect connector J1 and J2 from the ECM.

d. At the machine harness for the ECM, measure the resistance between connector J2-35 (710-GN) and J2-24 (G939-PK).

EXPECTED RESULT: There should be continuity (less than 5.0 ohms resistance).

RESULTS:

* OK - Resistance is less than 5.0 ohms; harness circuit resistance is correct. Go to Step 3.
* NOT OK - Resistance is greater than 5000 ohms; the machine harness is faulty. Wire 710-GN or G939-PK is open within the machine harness; between the speed sensor and the ECM. Check the continuity of 710-GN and G939-PK. Repair or replace the machine harness. STOP.

STEP 3. Check For Shorted Harness.

a. The disconnect and key start switches remain in the OFF position.

b. Disconnect the machine harness from the sensor and from J1 and J2 of the ECM.

c. At the machine harness connector for the sensor remove the jumper from contact C to contact B.

d. At the machine harness connector for the ECM, measure the resistance between connector J2 contact 35 (wire 710-GN) and all other connector contacts.

EXPECTED RESULT: The resistance should be greater than 5000 ohms for each measurement.

RESULTS:

* OK - Resistance is greater than 5000 ohms; harness circuit resistance is correct. Go to Step 4.
* NOT OK: - Resistance is less than 5000 ohms; the machine harness is faulty. Wire 710-GN is shorted within the machine harness; between the speed sensor and the ECM. Repair or replace the machine harness.

STEP 4. Replace Sensor.- Replace the sensor; see the subject Transmission Output Speed Sensor Replacement. After replacement, check to see if the fault still remains.

a. Turn the disconnect and key start switches to the ON position.

b. Start the engine and run at low idle.

c. Put the respective FMI 00 or FMI 01 fault on-hold. Observe and see if the fault is active.

EXPECTED RESULT: The fault indicator for FMI 00 or FMI 01 is not active.

RESULTS:

* OK - Fault is no longer active; the sensor was faulty. The fault is corrected. STOP.
* NOT OK - Fault is still active; the fault remains present. It is unlikely that the ECM is faulty. Perform the previous Steps again. If the cause is not found, replace the ECM. See the subject ECM Replacement. STOP.

CID 0248 Procedure - CAT Data Link

FMI 12

This fault is recorded when the power train Electronic Control Module (ECM) cannot send or does not receive expected information from other ECM modules via the data link at connector J1, contact 3 (wire 892-BR) and contact 9 (wire 893-GN).

The CAT data link is an input and an output of the power train ECM at connector J1, contact 3 (wire 892-BR) and contact 9 (wire 893-GN). The purpose of the data link is to communicate with other electronic control module, such as VIMS monitoring system, the engine ECM, and diagnostic service tools. The data link is not a visible component; it consists of internal ECM circuits and the connecting harness wiring. The data link is bidirectional which allows the power train ECM to receive and send information.

STEP 1. Inspect The Connector.

Ensure that the power train ECM connector J1 is tight, the wire has good contact, check for nicks or signs of abrasion in the insulation, check for moisture at the connector and check for dirty or corroded contacts.

EXPECTED RESULT: The original condition no longer exists.

RESULTS:

* OK - A machine harness connection was faulty. There could have been an intermittent connection in the data link circuits of the machine harness. Watch for a recurrence of this fault. STOP.
* NOT OK - The harness could be faulty. Proceed to Step 2.

STEP 2. Check Cat Data Link For Open Circuit.

a. Turn the disconnect and key start switch to the OFF position.

b. All related ECM's remain disconnected from the machine harness.

c. At the power train ECM measure the resistance from connector J1, contact 3 (wire 892-BR) to the corresponding connectors:

d. At the power train ECM measure the resistance from connector J1, contact 9 (wire 893-GN) to the corresponding connector contacts:

e. At the VIMS Interface Module #1 measure the resistance from contact 24 (wire 882-PK) to the VIMS Interface Module #2, contact 22 (wire 882-PK).

f. At the VIMS Main Module measure the resistance from contact 23 (wire 883-GY) to the VIMS Interface Module #2, contact 21 (wire 883-GY).

EXPECTED RESULT: There should be less than 5 ohms resistance for each measurement.

RESULTS:

* REPAIR COMPLETE - The Cat data link circuit in the machine harness is correct. It is unlikely that the engine ECM is faulty. Perform the previous Steps again. STOP.
* NOT OK - The data link circuit connector J1, contact 3 (wire 892-BR) or contact 9 (893-GN) is open in the machine harness. Repair Or Replace Machine Harness. If conditions are not resolved, proceed to Step 3.

STEP 3. Check For Cat Data Link Circuit Short To Ground.

a. Turn the disconnect and key start switch to the OFF position.

b. Inspect the machine harness connectors related to the CAT Data Link circuits. Ensure that the connector contacts are clean and connectors are tight. If necessary repair or replace the machine harness connectors.

c. Disconnect the machine harness from all modules.

d. At the machine harness connector for the engine ECM, measure the resistance between the CAT data link circuit connector J1, contact 3 and 9 to all possible sources of ground. The possible sources of ground are connector J1, contact 5, 11, 29, 30, connector J2, contact 5, 7, 17, 27, 39 and frame ground.

EXPECTED RESULT: Each resistance should be greater than 5000 ohms for each measurement.

RESULTS:

* OK - The machine harness is correct. Proceed to Step 4.
* NOT OK - There is a short in the machine harness. The short is between the circuit with the resistance less than 5000 ohms and contact 3 (wire 892-BR) or contact 9 (893-GN). Repair Or Replace Machine Harness. If conditions are not resolved, proceed to Step 6.

STEP 4. Check For Cat Data Link Short Circuit To Positive Voltage.

a. The disconnect and key start switch remain OFF.

b. All modules remain disconnected from the machine harness.

c. At the machine harness connector for the engine ECM, measure the resistance between the CAT data link circuits (contacts J1-3 and J1-9) and all possible sources of positive voltage. The possible sources of positive voltage of connector J1 are contacts 2, 4, 6, 7, 8, 13, 14, 17, 18, 19, 20, 22, 23, 24, 25, 26, 27, 31, 32, 35, 36, 38 and 40. The possible sources of positive voltage of connector J2 are contacts 1, 2, 8, 9, 14, 16, 19, 20, 23, 24, 25, 26, 30, 31, 32, 36, 37 and 38.

EXPECTED RESULT: The resistance should be greater than 5000 ohms for each measurement.

RESULTS:

* OK - The machine harness is correct. Proceed to Step 5.
* NOT OK - There is a short in the machine harness. The short is between the circuit with the resistance less than 5000 ohms and connector J1, contact 3 (wire 892-BR) or contact 9 (893-GN). Repair Or Replace Machine Harness. If conditions are not resolved, proceed to Step 6.

STEP 5. Check Harness Connection.

a. The disconnect switch remains OFF.

b. Remove the jumper of the previous Step.

c. Reconnect the power train ECM and the VIMS Main Module to the machine harness.

d. Turn the disconnect and the key start switch to the ON position.

EXPECTED RESULT: The original fault no longer exists.

RESULTS:

* OK - A machine harness connection was faulty. There could have been an intermittent connection in the data link circuits of the machine harness. Watch for a recurrence of this fault. STOP.
* NOT OK - Proceed to Step 6.

STEP 6. Check Monitor.

a. Turn the disconnect switch and the key start switch to the OFF position.

b. Disconnect the machine harness from the VIMS Main Module.

c. Turn the disconnect switch and the key start switch to the ON position.

EXPECTED RESULT: The original condition no longer exists.

RESULTS:

* OK - The monitor is faulty. Replace the VIMS display monitor.
* NOT OK - Replace the power train ECM. ECM replacement must be done in a specific manner. See the topic ECM Replacement. STOP.

CID 0254 Procedure - Electronic Control Module (ECM)

FMI 12

This fault is recorded when the ECM reads a fault internal to the ECM itself. The only possible cause of this fault is that the ECM is faulty. There are no user serviceable parts within the ECM. Replace the ECM. See the topic ECM Replacement.

CID 0590 Procedure - Cat Data Link Communication With Engine Electronic Control Module (ECM)

FMI 09

This fault is recorded when the power train Electronic Control Module (ECM) cannot communicate with the engine ECM via the Cat Data Link. The update rate from the engine ECM is not correct. Check to see if a data link fault (CID 0248 FMI 12) exists. If a data link fault is present, correct it. If the fault is not present check the engine ECM for proper operation and active service codes.

The CAT data link is an input and an output of all modules. The purpose of the data link is to link communications with all modules and service tools. The data link is not a visible component; it consists of internal control circuits and the connecting harness wiring.

STEP 1. Check Software Compatibility.

For the correct software part numbers, refer to the Electronics Groups in the 994D Wheel Loader Parts Book, SEBP2993.

EXPECTED RESULT: The software is compatible.

RESULTS:

* OK - Proceed to Step 2.
* NOT OK - The software is NOT compatible, install the correct software. If any module(s) have been replaced, ensure that the correct part number was used. If conditions are not resolved, proceed to Step 2.

STEP 2. Check +Battery Circuit At Engine ECM Connectors.

a. Turn the disconnect and key start switch to the OFF position.

b. Disconnect connector J1 from the engine ECM.

c. Turn the disconnect and key start switch to the ON position.

d. At the connector J1, measure the voltage from contact 23 (wire 113-OR) to contact 5 or 11 (wire 229-BK).

EXPECTED RESULT: The voltage should measure 18 to 35 DCV.

RESULTS:

* OK - The engine ECM is receiving the correct power. Proceed to Step 3.
* NOT OK - The engine ECM is NOT receiving the correct power. Check to be sure there is a proper ground. If ground is OK then repair power circuit. (Also check circuit breakers). The power circuit connector J1, contact 23 (wire 113-OR) to the engine ECM in the machine harness is faulty. Repair Power Circuit To engine ECM. If conditions are not resolved, proceed to Step 4.

STEP 3. Check For Cat Data Link Circuit Short To Ground.

a. Turn the disconnect and key start switch to the OFF position.

b. Inspect the machine harness connectors related to the CAT Data Link circuits. Ensure that the connector contacts are clean and connectors are tight. If necessary repair or replace the machine harness connectors.

c. Disconnect the machine harness from all modules.

d. At the machine harness connector for the engine ECM, measure the resistance between the CAT data link circuit connector J1, contact 3 and 9 to all possible sources of ground. The possible sources of ground are connector J1, contact 5, 11, 29, 30, connector J2, contact 5, 7, 17, 27, 39 and frame ground.

EXPECTED RESULT: Each resistance should be greater than 5000 ohms for each measurement.

RESULTS:

* OK - The machine harness is correct. Proceed to Step 4.
* NOT OK - There is a short in the machine harness. The short is between the circuit with the resistance less than 5000 ohms and contact 3 (wire 892-BR) or contact 9 (893-GN). Repair Or Replace Machine Harness. If conditions are not resolved, proceed to Step 6.

STEP 4. Check For Cat Data Link Short Circuit To Positive Voltage.

a. The disconnect and key start switch remain OFF.

b. All modules remain disconnected from the machine harness.

c. At the machine harness connector for the engine ECM, measure the resistance between the CAT data link circuits (contacts J1-3 and J1-9) and all possible sources of positive voltage. The possible sources of positive voltage of connector J1 are contacts 2, 4, 6, 7, 8, 13, 14, 17, 18, 19, 20, 22, 23, 24, 25, 26, 27, 31, 32, 35, 36, 38 and 40. The possible sources of positive voltage of connector J2 are contacts 1, 2, 8, 9, 14, 16, 19, 20, 23, 24, 25, 26, 30, 31, 32, 36, 37 and 38.

EXPECTED RESULT: The resistance should be greater than 5000 ohms for each measurement.

RESULTS:

* OK - The machine harness is correct. Proceed to Step 5.
* NOT OK - There is a short in the machine harness. The short is between the circuit with the resistance less than 5000 ohms and connector J1, contact 3 (wire 892-BR) or contact 9 (893-GN). Repair Or Replace Machine Harness. If conditions are not resolved, proceed to Step 6.

STEP 5. Check Cat Data Link For Open Circuit.

a. The disconnect switch remains OFF.

b. All related ECM's remain disconnected from the machine harness.

c. At the engine ECM measure the resistance from connector J1, contact 3 (wire 892-BR) to the corresponding connectors:

d. At the engine ECM measure the resistance from connector J1, contact 9 (wire 893-GN) to the corresponding connector contacts:

e. At the VIMS Interface Module #1 measure the resistance from contact 24 (wire 882-PK) to the VIMS Interface Module #2, contact 22 (wire 882-PK).

f. At the VIMS Main Module measure the resistance from contact 23 (wire 883-GY) to the VIMS Interface Module #2, contact 21 (wire 883-GY).

EXPECTED RESULT: There should be less than 5 ohms resistance for each measurement.

RESULTS:

* REPAIR COMPLETE - The Cat data link circuit in the machine harness is correct. It is unlikely that the engine ECM is faulty. Perform the previous Steps again. STOP.
* NOT OK - The data link circuit connector J1, contact 3 (wire 892-BR) or contact 9 (893-GN) is open in the machine harness. Repair Or Replace Machine Harness. If conditions are not resolved, proceed to Step 6.

STEP 6. Repair Or Replace Engine ECM.

ECM replacement must be done in a specific manner. Specific instructions should be followed. For instructions to replace the engine ECM, refer to Troubleshooting 3500B Engines For Caterpillar Built Machines, RENR1310.

EXPECTED RESULT: The original condition no longer exists.

RESULTS:

* REPAIR COMPLETE - STOP.
* NOT OK - The original condition still exists, recheck the system. STOP.

FMI 12

This fault is recorded when the power train Electronic Control Module (ECM) does not receive enough parameters from the engine ECM via the CAT data link.

The CAT data link is an input and an output of all modules. The purpose of the data link is to link communications with all modules and service tools. The data link is not a visible component; it consists of internal control circuits and the connecting harness wiring.

STEP 1. Check Software Compatibility.

For the correct software part numbers, refer to the Electronics Groups in the 994D Wheel Loader Parts Book, SEBP2993.

EXPECTED RESULT: The software is compatible.

RESULTS:

* OK - The original condition still exists, recheck the system. STOP.
* NOT OK - The software is NOT compatible, install the correct software. If any module(s) have been replaced, ensure that the correct part number was used. STOP.

CID 0603 Procedure - Impeller Clutch Pressure Sensor


Impeller Clutch Pressure Sensor Schematic

FMI 03

This fault is recorded when the ECM reads the impeller clutch pressure signal (wire E705-BU) as shorted to +battery (FMI 03). The impeller clutch pressure sensor is a PWM type of sensor. The impeller clutch pressure signal wire (wire E705-BU) connects to connector J2 contact 6 of the ECM connector.

Service Notes: Ensure that the CID 0603 / FMI 03 fault is active.

STEP 1. Check ECM And Harness.

a. Turn the disconnect and key start switch to the ON position.

b. Disconnect the machine harness from the sensor.

c. At the machine harness connector for the sensor, measure the voltage (DCV) between signal contact C and ground contact B.

EXPECTED RESULT: Measured voltage is 8.0 ± 0.5 DCV.

RESULTS:

* OK - ECM and harness are correct. The sensor and/or it's harness are defective. Check the harness of the sensor. If no defect is found in the sensor harness, replace the sensor. STOP
* NOT OK - Voltage is NOT 8.0 ± 0.5 DCV; ECM or harness is defective. Go to Step 2.

STEP 2. Check Harness Ground Circuit.

a. The sensor remains disconnected.

b. Turn the disconnect and key start switch to the OFF position.

c. Disconnect the machine harness from the ECM.

d. At the machine harness connector for the sensor, measure the resistance between ground contact B and frame ground.

EXPECTED RESULT: Resistance measured is greater than 2.0 ohms.

RESULTS:

* OK - The ground circuit in the harness is defective. There is an open circuit between ground contact B and frame ground. Repair or replace the machine harness. STOP.
* NOT OK - Resistance is less than 2.0 ohms; harness resistance is correct. Go to Step 3.

STEP 3. Check For Shorted Harness.

a. The sensor and ECM remain disconnected from the machine harness.

b. The disconnect switch remains OFF.

c. At the machine harness connector for the sensor, measure the resistance between signal contact C and +battery contact A.

EXPECTED RESULT: Resistance measured is less than 5000 ohms.

RESULTS:

* OK - The machine harness is defective. There is a short between the +battery circuit and the signal circuit in the machine harness. Repair or replace the machine harness. STOP.
* NOT OK - Resistance is greater than 5000 ohms; harness circuit resistance is correct. Go to Step 4.

STEP 4. Check For Open Harness.

a. The sensor and ECM remain disconnected from the machine harness.

b. The disconnect switch remains OFF.

c. Check the continuity of the signal circuit from connector J2 contact 6 of the machine harness connector to contact C of the sensor machine harness connector.

EXPECTED RESULT: There is NO continuity.

RESULTS:

* OK - The signal circuit is defective. The signal circuit is open in the machine harness. Repair or replace the machine harness. STOP.
* NOT OK - There is continuity; the signal circuit is correct. Go to step 4. The ECM is defective. Replace the ECM; see ECM Replacement. STOP.

FMI 04

This fault is recorded when the ECM reads the impeller clutch pressure signal (wire E705-BU) as shorted to ground (FMI 04). The impeller clutch pressure sensor is a PWM type of sensor. The impeller clutch pressure wire (wire E705-BU) connects to connector J2 contact 6 of the ECM connector.

Service Notes: Ensure that the CID 0603 / FMI 04 fault is active.

NOTE: Step 1 can create a CID 0603 FMI 03 fault. When all harnesses are reconnected, this fault is shown as not active, it will be logged. Clear the CID 0603 FMI 03 fault after this procedure is completed.

STEP 1. Check Sensor.

a. Ensure that the CID 0603 FMI 04 fault is active.

b. Observe the status of the fault.

c. Disconnect the machine harness from the sensor.

EXPECTED RESULT: If the sensor is not the cause of the fault, the fault remains active. If the sensor is faulty, fault becomes inactive.

RESULTS:

* OK - Fault is active; indicates the fault remains present. The sensor is not causing the fault. Go to Step 2.
* NOT OK - Fault is inactive; indicates the fault is no longer present. The sensor is defective. Replace the sensor, also see the topic PWM Sensor Tests. STOP.

STEP 2. Check Harness.

a. The sensor remains disconnected from the machine harness.

b. Turn the disconnect switch to the OFF position.

c. Disconnect the machine harness from the ECM.

d. At the machine harness connector for the ECM, measure the resistance between signal contact C and frame ground.

EXPECTED RESULT: The resistance should be greater than 5000 ohms.

RESULTS:

* OK - The machine harness circuit resistance is correct. The ECM is defective. Replace the ECM; see ECM Replacement. STOP.
* NOT OK - Resistance is less than 5000 ohms; the machine harness is defective. There is a short between frame ground and the signal circuit in the machine harness. Repair or replace the machine harness. STOP.

CID 0143 Procedure - Neutralizer Pressure Switch CID 0623 Procedure, STIC Direction Switch; CID 0626 Procedure, Steering/Transmission Lock Switch; CID 0627 Procedure, Parking Brake Pressure Switch; CID 0628 Procedure, Quick-Shift Switch

FMI 03

Each of these switches has two inputs to the ECM; N/O and N/C. There are three inputs for the direction switch. During normal operation, one of the inputs is open and the other input is grounded. If both inputs are the same, the ECM detects a fault. This fault is detected when both inputs are either open or shorted to +battery. Before performing this procedure use the Switch Continuity chart to determine the connector and contact that corresponds to the faulty circuit.

Service Notes: Ensure that the desired fault CID FMI 03 is active.

NOTE: Step 1 can create other faults that the ECM detects. Ignore these created faults and clear them when this fault is corrected.

STEP 1. Check For Open Circuit.

a. Turn the disconnect switch and the key start switch to the OFF position.

b. Disconnect the machine harness from the ECM.

c. At the machine harness connector for the ECM, check the continuity to ground of the N/C contact and the N/O contact with the switch activated and not activated. See the Switch Continuity chart.

EXPECTED RESULT: Continuity check does not agree with the chart.

RESULTS:

* YES - Continuity check does NOT agree with chart; the harness or switch is faulty. Go to Step 2.
* NO - Continuity check agrees with chart; Go to Step 3.

STEP 2. Check Switch.

a. Disconnect the machine harness from the switch.

b. Check the continuity to ground of the N/C contact and the N/O contact with the switch activated and not activated. See the Switch Continuity Chart.

EXPECTED RESULT: Continuity check does not agree with the chart.

RESULTS:

* YES - Continuity check does not agree with the chart; switch is faulty. Repair or replace the switch.
* NO - Continuity check agrees with the chart; Repair or replace the machine harness. STOP.

STEP 3. Check For Short To +B.

At the machine harness connector for the ECM, check the continuity from each of the switch contact wires to contacts J1-1, 6, 40 and J2-12.

EXPECTED RESULT: Continuity exists between one of the sources of battery voltage and the switch circuit.

RESULTS:

* YES - Continuity exists between one of the sources of battery voltage. Machine harness is faulty. Repair or replace machine harness. STOP.
* NO - Continuity does not exist between one of the sources of battery voltage and the switch circuit. Machine harness is correct. It is unlikely that an ECM is faulty. Perform the previous steps again. If the cause is not found, replace the ECM. See the subject ECM Replacement. STOP.

FMI 04

This fault is recorded when the status of both the N/O and N/C inputs of the switch are grounded.

Service Notes: Ensure that the desired fault CID / FMI 04 fault active.

NOTE: Step 1 can create other faults that the ECM detects. Ignore these created faults and clear them when this fault is corrected.

STEP 1. Check Switch.

a. Ensure that the fault is active.

b. Observe the ON/OFF status of the fault.

c. Disconnect the connector of the switch from the machine harness.

EXPECTED RESULT: Active fault changes from 04 to 03.

RESULTS:

* OK - The switch or it's harness is failed. Repeat this Step (Step 1) to verify the switch failure. Repair or replace the switch and or it's harness.

NOTE: The switches within the STIC controller are not individually serviceable. The three switches are serviced as one unit.

* NOT OK - Fault present indicator remains ON; the switch is not the cause of this fault. Go to Step 2.

STEP 2. Check Harness Circuit This Step checks the continuity of the entire harness circuit that is faulty; including the switch which was previously checked in Step 1.

a. Turn the disconnect switch to OFF position.

b. Connect the switch of Step 1 to the machine harness.

c. Disconnect the machine harness from the ECM.

d. At the machine harness connector for the ECM, check the continuity to ground of the N/C contact and the N/O contact with the switch activated and not activated. See the Switch Continuity chart.

EXPECTED RESULT: Continuity check does not agree with the chart.

RESULTS:

* YES - Continuity check does NOT agree with chart; the harness circuit is faulty. There is a short to ground in the machine harness between the ECM and the switch. Repair or replace the machine harness.
* NO - Continuity check agrees with chart; harness circuit is correct. It is unlikely that an electronic control is faulty. Perform the previous Steps again. If the cause is not found, replace the ECM. See the subject ECM Replacement. STOP.

CID 0144 Procedure - Backup Alarm Relay CID 0444 Procedure, Start Relay; CID 0678 Procedure, Impeller Clutch Solenoid Valve; CID 0679 Procedure, Lockup Clutch Solenoid Valve; CID 1401 Procedure, Transmission Clutch 1 Solenoid Valve; CID 1402 Procedure, Transmission Clutch 2 Solenoid Valve; CID 1403 Procedure, Transmission Clutch 3 Solenoid Valve; CID 1404 Procedure, Transmission Clutch 4 Solenoid Valve; CID 1405 Procedure, Transmission Clutch 5 Solenoid Valve;

FMI 03

This fault is recorded when the ECM reads the voltage of the solenoid circuit as above normal (short to +battery).

Service Note: Ensure that the service code CID FMI for the solenoid is active. Before performing this procedure, use the preceding Solenoid Information chart to determine the connector contact No. and the wire No. that corresponds to the failed circuit.

STEP 1. Check Solenoid Signal Circuit For Short To +Battery.

a. Turn the key start and disconnect switch to the OFF position.

b. Disconnect the machine harness from the suspected solenoid.

c. Disconnect the machine harness connectors J1 and J2 from the ECM.

d. At machine harness connector J1 and J2, measure the resistance from the solenoid signal contact (see chart) to all possible sources of +battery. The possible sources of positive voltage are connector J1 contacts 1, 4, 6, 8, 11, 17, and 40. For connector J2 contacts 1, 7, 8, 13, 19 and 37.

EXPECTED RESULT: Each resistance should be greater than 5000 ohms.

RESULTS:

* OK - The machine harness is correct. Proceed to next step.
* NOT OK - There is a short in the machine harness. The short is between the solenoid signal contact (see chart) and the circuit with low resistance measurement. Repair or replace the machine harness. STOP.

STEP 2. Check If Fault Remains.

a. Inspect and clean the contacts of the harness connectors.

b. Reconnect all harness connectors.

c. Turn the key start switch to the ON position.

d. Enter service mode of the VIMS Monitoring System and clear all inactive faults.

e. Attempt to operate the machine in all gears, all gears may not be available.

f. Stop the machine and engage the parking brake.

g. Check to see if CID FMI service code for the solenoid is active.

EXPECTED RESULT: Is the CID FMI service code for the solenoid active?

RESULTS:

* YES - The fault has not been corrected. It is unlikely that the ECM is faulty. Perform the previous Steps again. If the cause of the fault is not found, replace the ECM. See the topic ECM Replacement. STOP.
* NO - Fault is NOT active; the fault does not exist at this time. The initial fault was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation. STOP.

FMI 05

This fault is recorded when the ECM reads the current of the solenoid as below normal (open circuit).

Service Note: Ensure that the service code CID FMI for the solenoid is active. Before performing this procedure, use the preceding Solenoid Information chart to determine the connector contact No. and the wire No. that corresponds to the failed circuit.

STEP 1. Check Solenoid Resistance.

a. Disconnect the machine harness from the suspected solenoid.

b. At the solenoid, measure the resistance between the two contacts of the solenoid connector.

EXPECTED RESULT: The resistance should be less than 15 ohms.

RESULTS:

* OK - The solenoid resistance is correct. Either the wire for solenoid signal or the solenoid return circuit (wire 975-WH) is open in the harness. Reconnect solenoid and go to Step 2.
* NOT OK - The solenoid is failed. Replace the solenoid. STOP.

STEP 2. Check Solenoid Circuit For Open.

a. Turn the key start and disconnect switch to the OFF position.

b. Disconnect the machine harness connectors J1 and J2 from the ECM.

c. At machine harness connector J1 or J2, measure the resistance from the solenoid signal contact (see chart) to J2-3 (return) or J1-7 (return).

EXPECTED RESULT: The resistance should be less than 15 ohms.

RESULTS:

* OK - The machine harness is correct. Suspect intermittent fault. Reconnect connector and recheck. Go to Step 3.
* NOT OK - There is an open circuit in the machine harness. The open is in the wire for the solenoid signal or in wire 975-WH of the machine harness. Check continuity on each of the circuits. Repair or replace the machine harness. STOP.

STEP 3. Check If Fault Remains.

a. Inspect and clean the contacts of the harness connectors.

b. Reconnect all harness connectors.

c. Turn the disconnect and key start switch to the ON position.

d. Operate the machine and see if the fault reappears.

e. Check to see if the CID FMI service code for the solenoid has recurred.

EXPECTED RESULT: Is the CID FMI for the solenoid still active?

RESULTS:

* YES - The fault has not been corrected. It is unlikely that the ECM is faulty. Perform the previous Steps again. If the cause of the fault is not found, replace the ECM. See the topic ECM Replacement. STOP.

NOTE: The ECM will not attempt to operate a solenoid that it detects as open circuit.

* NO - Fault is NOT active; the fault does not exist at this time. The initial fault was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation. STOP.

FMI 06

This fault is recorded when the ECM reads the current of the solenoid circuit as above normal (short to ground).

Service Note: Ensure that the service code CID FMI for the solenoid is active. Before performing this procedure, use the preceding Solenoid Information chart to determine the connector contact No. and the wire No. that corresponds to the failed circuit.

STEP 1. Check Solenoid Resistance.

a. Turn the key start and disconnect switch to the OFF position.

b. Disconnect the machine harness from the suspected solenoid.

c. At the solenoid, measure the resistance between the two contacts of the solenoid connector.

EXPECTED RESULT: The resistance should be less than 15 ohms.

RESULTS:

* OK - The solenoid resistance is correct. Go to Step 2.
* NOT OK - The solenoid is failed. Replace the solenoid. STOP.

STEP 2. Check Solenoid For Short To Ground.

The disconnect and key start switch remain in the OFF position. The solenoid remains disconnected from the machine harness.

a. Measure the resistance from each solenoid contact to frame ground.

EXPECTED RESULT: Each resistance should be greater than 5000 ohms.

RESULTS:

* OK - The solenoid and it's harness are correct. The fault is in the machine harness Go to Step 3.
* NOT OK - The solenoid has failed. Replace the solenoid. STOP.

STEP 3. Check Solenoid Signal Circuit For Short To Ground. The machine harness remains disconnected from the solenoid.

a. The disconnect and key start switch remain in the OFF position.

b. Disconnect the machine harness connectors J1 and J2 from the ECM.

c. At machine harness connector J1 or J2, measure the resistance from the solenoid signal contact (see chart) to all possible sources of ground. The possible ground sources are: J1 contact 2, 5, 7, 15, 16, J2 contact 3 and frame ground.

EXPECTED RESULT: Each resistance should be greater than 5000 ohms.

RESULTS:

* OK - The machine harness is correct. Proceed to next step.
* NOT OK - There is a short in the machine harness. The short is between the wire for the solenoid signal (see chart) and the circuit with low resistance measurement. Repair or replace the machine harness. STOP.

STEP 4. Check If Fault Remains.

a. Inspect and clean the contacts of the harness connectors.

b. Reconnect all harness connectors.

c. Turn the disconnect and key start switch to the ON position.

d. Operate the machine.

e. Stop the machine and engage the parking brake.

f. Check to see if the CID FMI service code for the solenoid is active.

EXPECTED RESULT: Is the CID FMI service code for the solenoid active?

RESULTS:

* YES - The fault has not been corrected. It is unlikely that the ECM is faulty. Perform the previous Steps again. If the cause of the fault is not found, replace the ECM. See the topic ECM Replacement. STOP.
* NO - Fault is NOT active; the fault does not exist at this time. The initial fault was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation. STOP.

FMI 07 - Only For: CID 0678 Impeller Clutch Solenoid Valve

This fault is recorded when the ECM determines that there is a impeller clutch pressure difference between what the ECM commands and what is actual read.

Example - The ECM send outs out an electrical command or output to the impeller clutch solenoid for a pressure of 5512 kPa (800 psi). This pressure is not sensed by the impeller clutch pressure sensor. This would indicate that there is something mechanically wrong with the impeller clutch hydraulic circuit.

FMI 13 - Only For: CID 0678 Impeller Clutch Solenoid Valve

This fault is recorded when the ECM determines that the transmission impeller clutch solenoid valve needs calibration. Once impeller clutch solenoid valve calibration has been performed successfully, this diagnostic code will disappear.

STEP 1. Perform The Impeller Clutch Solenoid Valve Calibration. Proceed to the topic Impeller Clutch Solenoid Valve Calibration. Perform the calibration. STOP.

CID 0650 Procedure - Monitoring System Broadcast Attachment Code

FMI 02

This fault is recorded when the power train Electronic Control Module (ECM) detects that a new attachment code has been loaded to the VIMS Main Module since the power train ECM was powered up.

The attachment code is a code that is entered into the monitoring system and is stored in the VIMS Main Module. The attachment code is an input of the VIMS Main Module and is used to identify what attachments a machine is equipped with. The attachment code tells the power train and engine ECM how to operate within the physical limits of the machine. If the attachment code does not match the actual attachments on the machine, a service code may be generated on the monitoring system.

STEP 1. Clear The Fault.

After a new attachment code has been entered into the VIMS Main Module, the Main Module must be reset.

Turn the key start switch OFF then back ON.

EXPECTED RESULT: The original condition no longer exists.

RESULTS:

* REPAIR COMPLETE - STOP.
* NOT OK - The original condition still exists, recheck the system. STOP.

FMI 09

This fault is recorded when the power train Electronic Control Module (ECM) does not receive the attachment code from the VIMS Main Module. Something is wrong with the VIMS Main Module or there is a CAT data link problem.

The attachment code is a code that is entered into the monitoring system and is stored in the VIMS Main Module. The attachment code is an input of the VIMS Main Module and is used to identify what attachments a machine is equipped with. The attachment code tells the power train and engine ECM how to operate within the physical limits of the machine. If the attachment code does not match the actual attachments on the machine, a service code may be generated on the monitoring system.

STEP 1. Check the Attachment Code.

Service program code: 67828 (MSTAT)

This service program allows the current attachment code to be viewed.

a. Ensure that the correct attachment code is entered into the service program.

b. On VIMS enter "MSTAT" then enter "OK".

c. Use the FORWARD arrow key, ">", to move through the list until ATTACHMENT CODE is displayed.

d. Use the list below to verify that the correct attachment code is being used.

EXPECTED RESULT: Attachment code is not correct.

RESULTS:

* OK - Enter correct attachment code. Proceed to Step 2.
* NOT OK - Attachment code is correct. Proceed to Step 3.

STEP 2. Check Software Compatibility.

For the correct software part numbers, refer to the Electronics Groups in the 994D Wheel Loader Parts Book, SEBP2993.

EXPECTED RESULT: The software is compatible.

Results:

* OK - Proceed to Step 3.
* NOT OK - The software is NOT compatible, install the correct software. If any module(s) have been replaced, ensure that the correct part number was used. If conditions are not resolved, proceed to Step 3.

STEP 3. Connector Inspection.

a. Ensure that the connectors are tight, the wire has good contact, check for nicks or signs of abrasion in the insulation, check for moisture at the connector and check for dirty or corroded contacts. Refer to Connector Inspection.

EXPECTED RESULT: The original condition no longer exists.

RESULTS:

* REPAIR COMPLETE - A machine harness connection was faulty. There could have been an intermittent connection in the data link circuits of the machine harness. Watch for a recurrence of this fault. STOP.
* NOT OK - Proceed to Step 4.

STEP 4. Check For Open CAT Data Link Circuit.

a. Turn the disconnect switch to the OFF position.

b. Disconnect connector J1 of the machine harness from the power train and the engine ECM.

c. Install a jumper at the Junction Block (located in the front of the electronics bay) from connector B1, contact 1 (wire 892-BR) to connector B2, contact 1 (wire 893-GN).

d. Check for continuity of the CAT data link from connector J1 contact 3 (wire 892-BR) to 9 (wire 893-GN) of the power train and the engine ECM; there should be continuity.

e. Disconnect the VIMS Main Module and check for continuity from contact 6 (wire 893-GN) to contact 7 (wire 892-BR); there should be continuity.

f. Disconnect the VIMS Interface Module #1 and check for continuity from contact 21 (wire 893-GN) to contact 22 (wire 892-BR).

g. Remove the jumpers from the previous steps.

EXPECTED RESULT: There was continuity in all of the previous checks.

RESULTS:

* OK - The CAT data link circuit resistance is correct. The power train ECM could be faulty. Before replacing the power train ECM, recheck the system, the ECM is usually not the cause of a fault. Proceed to Step 5.
* NOT OK - The machine harness is faulty. There is an open circuit at the wire that has NO continuity. Repair or replace the faulty harness wire. If conditions are not resolved, proceed to Step 5.

STEP 5. VIMS Main Module.

VIMS Main Module replacement must be done in a specific manner. Specific instructions should be followed. Refer to VIMS Service Manual, SENR6059 for VIMS replacement.

EXPECTED RESULT: The original condition no longer exists.

RESULTS:

* REPAIR COMPLETE - STOP.
* NOT OK - The original condition still exists, recheck the system. STOP.

FMI 12

This fault is recorded when the Main Module is sending an attachment code that the power train Electronic Control Module (ECM) does NOT recognize. This service code is caused by an incorrect attachment code or an incorrect ECM has been installed on the machine.

The attachment code is a code that is entered into the monitoring system and is stored in the VIMS Main Module. The attachment code is an input of the VIMS Main Module and is used to identify what attachments a machine is equipped with. The attachment code tells the power train and engine ECM how to operate within the physical limits of the machine. If the attachment code does not match the actual attachments on the machine, a service code may be generated on the monitoring system.

STEP 1. Check Software Compatibility.

For the correct software part numbers, refer to the Electronics Groups in the 994D Wheel Loader Parts Book, SEBP2993.

EXPECTED RESULT: The software is compatible.

RESULTS:

* OK - The original condition still exists, recheck the system. STOP.
* NOT OK - The software is NOT compatible, install the correct software. If any module(s) have been replaced, ensure that the correct part number was used. STOP.

CID 0672 Procedure - Torque Converter Output Speed Sensor


Torque Converter Output Speed Sensor Schematic

FMI 00 And FMI 01

The torque converter output speed sensor measures the rotational speed and direction of the shaft between the torque converter and the transmission.

This fault is recorded when the ECM reads the torque converter speed signal (wire 452-PU) as too high (FMI 00) or too low (FMI 01). The torque converter output speed sensor is a frequency type of sensor. The torque converter speed signal wire (wire 452-PU) connects to connector J2 contact 38 of the ECM connector. This troubleshooting procedure is for either an FMI 00 or FMI 01 fault.

NOTE: If a + 10V sensor supply fault is present (CID 0041), correct it prior to proceeding with this CID 0672 fault. For proper operation of the torque converter output speed sensor, it must be receiving supply power of 10.0 ± 0.5 DCV from the ECM.

Service Notes: Ensure that the CID 0672 FMI 00 or CID 0672 FMI 01 fault active. The CID 0672 faults remain present until the ECM reads a good speed signal. Therefore the engine must be started and a good signal received before the ECM declares the fault not present.

STEP 1. Check Supply Voltage - Disconnect Nothing. Troubleshoot "as is" before disconnecting any circuits.

a. At the sensor, identify contact A, wire 709-OR (+10V) contact B, wire G939-PK (ground) and contact C, wire 452-PU (signal).

b. Turn the disconnect switch and the key start switch to the ON position.

c. Using 7X-1710 Cable Probe and measure the voltage between wire 709-OR (+V) and wire G939-PK (ground).

EXPECTED RESULT: The voltage measured is 10.0 ± 0.5 DCV;

RESULTS:

* OK - The sensor supply voltage is correct. Go to Step 2.
* NOT OK - Voltage is NOT 10.0 ± 0.5 DCV; there is a fault. Check for open harness between the sensor and the ECM. Also see the procedures for CID 0041 (sensor supply). STOP.

STEP 2. Check For Open Harness.

a. The disconnect and key start switches remain in the OFF position.

b. Disconnect connector J1 and J2 from the ECM.

c. At the machine harness connector for the sensor place a jumper from contact C to contact B.

d. At the machine harness for the ECM, measure the resistance between connector J2-38 (452-PU) and J1-15 (G939-PK).

EXPECTED RESULT: There should be continuity (less than 5.0 ohms resistance).

RESULTS:

* OK - Resistance is less than 5.0 ohms; harness circuit resistance is correct. Go to Step 3.
* NOT OK - Resistance is greater than 5000 ohms; the machine harness is faulty. Wire 452-PU or G939-PK is open within the machine harness; between the speed sensor and the ECM. Check the continuity of 452-PU and G939-PK. Repair or replace the machine harness. STOP.

STEP 3. Check For Shorted Harness.

a. The disconnect and key start switches remain in the OFF position.

b. Disconnect the machine harness from the sensor and from J1 and J2 of the ECM.

c. At the machine harness connector for the sensor remove the jumper from contact C to contact B.

d. At the machine harness connector for the ECM, measure the resistance between connector J2 contact 38 (wire 452-PU) and all other connector contacts.

EXPECTED RESULT: The resistance should be greater than 5000 ohms for each measurement.

RESULTS:

* OK - Resistance is greater than 5000 ohms; harness circuit resistance is correct. Go to Step 4.
* NOT OK: - Resistance is less than 5000 ohms; the machine harness is faulty. Wire 452-PU is shorted within the machine harness; between the speed sensor and the ECM. Repair or replace the machine harness.

STEP 4. Replace Sensor. - Replace the sensor; see the subject Torque Converter Output Speed Sensor Replacement. After replacement, check to see if the fault still remains.

a. Turn the disconnect and key start switches to the ON position.

b. Start the engine and run at low idle.

c. Put the respective FMI 00 or FMI 01 fault on-hold. Observe and see if the fault is active.

EXPECTED RESULT: The fault indicator for FMI 00 or FMI 01 is not active.

RESULTS:

* OK - Fault is no longer active; the sensor was faulty. The fault is corrected. STOP.
* NOT OK - Fault is still active; the fault remains present. It is unlikely that the ECM is faulty. Perform the previous Steps again. If the cause is not found, replace the ECM. See the subject ECM Replacement. STOP.

CID 0826 Procedure - Torque Converter Oil Temperature Sensor


Torque Converter Oil Temperature Sensor Schematic

FMI 03

This fault is recorded when the ECM reads the torque converter oil temperature signal (wire 443-YL) as shorted to +battery (FMI 03). The torque converter oil temperature sensor is a PWM type of sensor. The torque converter oil temperature signal wire (wire 443-YL) connects to connector J2 contact 5 of the ECM connector.

Service Notes: Ensure that the CID 0826 / FMI 03 fault is active.

STEP 1. Check ECM And Harness.

a. Turn the disconnect and key start switch to the ON position.

b. Disconnect the machine harness from the sensor.

c. At the machine harness connector for the sensor, measure the voltage (DCV) between signal contact C and ground contact B.

EXPECTED RESULT: Measured voltage is 8.0 ± 0.5 DCV.

RESULTS:

* OK - ECM and harness are correct. The sensor and/or it's harness are defective. Check the harness of the sensor. If no defect is found in the sensor harness, replace the sensor. STOP
* NOT OK - Voltage is NOT 8.0 ± 0.5 DCV; ECM or harness is defective. Go to Step 2.

STEP 2. Check Harness Ground Circuit.

a. The sensor remains disconnected.

b. Turn the disconnect and key start switch to the OFF position.

c. Disconnect the machine harness from the ECM.

d. At the machine harness connector for the sensor, measure the resistance between ground contact B and frame ground.

EXPECTED RESULT: Resistance measured is greater than 2.0 ohms.

RESULTS:

* OK - The ground circuit in the harness is defective. There is an open circuit between ground contact B and frame ground. Repair or replace the machine harness. STOP.
* NOT OK - Resistance is less than 2.0 ohms; harness resistance is correct. Go to Step 3.

STEP 3. Check For Shorted Harness.

a. The sensor and ECM remain disconnected from the machine harness.

b. The disconnect switch remains OFF.

c. At the machine harness connector for the sensor, measure the resistance between signal contact C and +battery contact A.

EXPECTED RESULT: Resistance measured is less than 5000 ohms.

RESULTS:

* OK - The machine harness is defective. There is a short between the +battery circuit and the signal circuit in the machine harness. Repair or replace the machine harness. STOP.
* NOT OK - Resistance is greater than 5000 ohms; harness circuit resistance is correct. Go to Step 4.

STEP 4. Check For Open Harness.

a. The sensor and ECM remain disconnected from the machine harness.

b. The disconnect switch remains OFF.

c. Check the continuity of the signal circuit from connector J2 contact 5 of the machine harness connector to contact C of the sensor machine harness connector.

EXPECTED RESULT: There is NO continuity.

RESULTS:

* OK - The signal circuit is defective. The signal circuit is open in the machine harness. Repair or replace the machine harness. STOP.
* NOT OK - There is continuity; the signal circuit is correct. Go to step 4. The ECM is defective. Replace the ECM; see ECM Replacement. STOP.

FMI 04

This fault is recorded when the ECM reads the torque converter oil temperature signal (wire 443-YL) as shorted to ground (FMI 04). The torque converter oil temperature sensor is a PWM type of sensor. The torque converter oil temperature signal (wire 443-YL) connects to connector J2 contact 5 of the ECM connector.

Service Notes: Ensure that the CID 0826 / FMI 04 fault is active.

NOTE: Step 1 can create a CID 0826 FMI 03 fault. When all harnesses are reconnected, this fault is shown as not active, it will be logged. Clear the CID 0826 FMI 03 fault after this procedure is completed.

STEP 1. Check Sensor.

a. Ensure that the CID 0826 FMI 04 fault is active.

b. Observe the status of the fault.

c. Disconnect the machine harness from the sensor.

EXPECTED RESULT: If the sensor is not the cause of the fault, the fault remains active. If the sensor is faulty, fault becomes inactive.

RESULTS:

* OK - Fault is active; indicates the fault remains present. The sensor is not causing the fault. Go to Step 2.
* NOT OK - Fault is inactive; indicates the fault is no longer present. The sensor is defective. Replace the sensor, also see the topic PWM Sensor Tests. STOP.

STEP 2. Check Harness.

a. The sensor remains disconnected from the machine harness.

b. Turn the disconnect switch to the OFF position.

c. Disconnect the machine harness from the ECM.

d. At the machine harness connector for the ECM, measure the resistance between signal contact C and frame ground.

EXPECTED RESULT: The resistance should be greater than 5000 ohms.

RESULTS:

* OK - The machine harness circuit resistance is correct. The ECM is defective. Replace the ECM; see ECM Replacement. STOP.
* NOT OK - Resistance is less than 5000 ohms; the machine harness is defective. There is a short between frame ground and the signal circuit in the machine harness. Repair or replace the machine harness. STOP.

Undetected Faults

The ECM does not detect all system faults; some are undetected. The following malfunctions are not detected by the ECM.

Backup Alarm Malfunction

The ECM applies power to the backup alarm relay whenever the ECM receives a reverse signal from the direction switch on the STIC controller.

Backup Alarm Always ON

If the backup alarms are always ON, the harness circuit is shorted to +battery or the ECM is failed.

STEP 1. Check Backup Alarm Signal Circuit For Short To +Battery.

a. Turn the key start switch to the OFF position.

b. Disconnect the machine harness from the backup alarm relay.

c. Disconnect the machine harness connectors J1 and J2 from the ECM.

d. At machine harness connector J2, measure the resistance from the J2-37 (backup alarm relay signal) to all possible sources of +battery. The possible sources of positive voltage are contacts J1-1, J1-6, J1-8, J1-11, J1-17, J1-18, J1-40, J2-1, J2-7, J2-8, J2-13, J2-19, and J2-37.

EXPECTED RESULT: Each resistance should be greater than 5000 ohms.

RESULTS:

* OK - The machine harness is correct. Proceed to next step.
* NOT OK - There is a short in the machine harness. The short is between wire 321-OR (backup alarm relay signal) and the circuit with the low resistance measurement. Repair or replace the machine harness. STOP.

STEP 2. Check If Fault Remains.

a. Inspect and clean the contacts of the harness connectors.

b. Reconnect all harness connectors.

c. Start the engine.

EXPECTED RESULT: Is the backup alarm always ON regardless of the position of the direction switch on the STIC controller.

RESULTS:

* YES - The fault has not been corrected. It is unlikely that the ECM is faulty. Perform the previous Steps again. If the cause of the fault is not found, replace the ECM. See the topic ECM Replacement. STOP.
* NO - Fault is NOT present; the fault does not exist at this time. The initial fault was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation. STOP.

Backup Alarm Always OFF

If the backup alarm is always off; the backup alarm is failed, the harness circuit is open, the harness circuit is shorted to ground, or the ECM is failed.

STEP 1. Check Backup Alarm.

a. Disconnect the backup alarm relay from the machine harness.

b. Use jumpers to connect the respective terminals of the backup alarm relay to +battery and ground.

EXPECTED RESULT: Does the backup alarm sound when power is applied?

RESULTS:

* YES - The backup alarm relay operates correctly. Proceed to next step.
* NO - The backup alarm relay is failed. Replace the backup alarm relay.

STEP 2. Check Backup Alarm Signal Circuit For Short To Ground. The machine harness remains disconnected from the backup alarm.

a. Turn the key start switch to the OFF position.

b. Disconnect the machine harness connectors J1 and J2 from the ECM.

c. At machine harness connector J2, measure the resistance from the J2-37 (backup alarm relay signal) to all possible sources of ground. The possible ground sources are: J1-2, J1-5, J1-7, J1-15, J1-16, J2-3 and frame ground.

EXPECTED RESULT: Each resistance should be greater than 5000 ohms.

RESULTS:

* OK - The machine harness is correct. Proceed to next step.
* NOT OK - There is a short in the machine. The short is between wire 321-OR (backup alarm relay signal) and the circuit with the low resistance measurement. Repair or replace the machine harness. STOP.

STEP 3. Check Backup Alarm Signal Circuit For Open.

a. Turn the key start switch to the OFF position.

b. Disconnect the machine harness connectors J1 and J2 from the ECM.

c. At the machine harness connector for the backup alarm relay, place a jumper from contact 1 to contact 2.

d. At machine harness connector J2, measure the resistance from J2-37 (backup alarm relay signal) to J2-3 (return).

EXPECTED RESULT: There should be continuity (less than 5.0 ohms resistance).

RESULTS:

* OK - The machine harness is correct. Proceed to next step.
* NOT OK - There is an open circuit in the machine harness. The open is in wire 321-OR (backup alarm relay signal) or in wire 975-WH (return) of the machine harness. Repair or replace the machine harness. STOP.

STEP 4. Check If Fault Remains.

a. Inspect and clean the contacts of the harness connectors.

b. Reconnect all harness connectors.

c. Start the engine.

EXPECTED RESULT: Does the backup alarm work while the direction switch on the STIC controller is in REVERSE?

RESULTS:

* YES - Fault is NOT present; the fault does not exist at this time. The initial fault was probably caused by a poor electrical connection or a short or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation. STOP.
* NO - The fault has not been corrected. It is unlikely that the ECM is faulty. Perform the previous Steps again. If the cause of the fault is not found, replace the ECM. See the topic ECM Replacement. STOP.

Starting System Malfunction

The ECM activates the start relay when the key start switch is in the START position and the direction switch is in the NEUTRAL position. The ECM detects a failure in the start relay circuit and the electrical system. Therefore check to see if a CID 0444 or CID 0168 fault exists and correct it before performing the following Key Start Switch Check. See the subject Detected Faults.

There are two possible starting system malfunctions that could be caused by the ECM system.

* Starting motor does not crank.
* Starting motor cranks whenever in neutral.

The same key start switch check covers either malfunction.

Key Start Switch Check

STEP 1. Check That A CID 0444 Fault Does Not Exist. If so, correct it before proceeding.

STEP 2. Check +Battery Connection To Key Start Switch.

a. Disconnect the ECM from the machine harness.

b. Turn the disconnect switch to the ON position.

c. Turn and hold the key start switch in the START position.

d. At the machine harness connector for the ECM, measure the voltage between connector J1 contact 40 (wire 307-OR) and contact 2 (ground).

EXPECTED RESULT: The voltage should be 9.0 to 32.0 DCV.

RESULTS:

* OK - +Battery voltage is present; go to Step 3.
* NOT OK - +Battery voltage is NOT present; the key start switch or machine harness is faulty. Check the key start switch and machine harness; replace if necessary. STOP.

STEP 3. Check Machine Harness For Short To Ground.

a. The ECM remains disconnected from the machine harness.

b. Turn the key start switch to the OFF position.

c. At the machine harness connector for the ECM, measure the voltage between connector J1 contact 40 (wire 307-OR) and contact 2 (ground).

EXPECTED RESULT: +Battery voltage should not be present.

RESULTS:

* YES - +Battery voltage is present; the key start switch or machine harness (wire 307-OR) is faulty. Check the key start switch and machine harness; replace if necessary. STOP.
* +Battery voltage is NOT present; the harness circuit operates correctly. It is unlikely that the ECM is faulty. Perform these Steps again. If the cause is not found, replace the ECM; see the subject ECM Replacement. STOP.

Lockup Clutch Malfunction

The ECM detects and diagnoses most faults of the lockup clutch function. However the ECM does not detect a fault with the lockup enable switch; connector J1 contact 32 (wire G765-GN).

1. If the lockup clutch function does not operate correctly, use Caterpillar Electronic Technician (ET) to check for a related fault. Correct any related faults that are shown; see the subject Detected Faults. The related faults are:

CID 0041 - +8V Sensor Supply

CID 0672 - Torque Converter Output Speed Sensor

CID 0679 - Lockup Clutch Solenoid Valve

2. If no related faults are present (or have been corrected); then check the lockup enable circuit. Disconnect machine harness connector J1 from the ECM. At machine harness connector J1 for the ECM, check contact 32 (wire G765-GN) for correct operation (open/grounded and shorts) with the switch in both positions. Refer to the Electrical System Schematic in the machine Service Manual.

* If the circuit works correctly and the problem remains, then the ECM is faulty. Replace the ECM; see the subject ECM Replacement.
* If the circuit works INCORRECTLY, then the machine harness or the switch is faulty. Troubleshoot the machine harness and the lockup enable switch. Disconnect the machine harness from the switch. Check the machine harness and the switch for continuity, shorts and open circuits. Refer to the Electrical System Schematic in the machine Service Manual. Repair or replace the faulty component (switch or harness).

Reduced Rimpull Malfunction

The ECM detects and diagnoses most faults of the reduced rimpull function. However the ECM does not detect a fault with the reduced rimpull ON/OFF switch.

1. If the reduced rimpull function does not operate correctly, check for a related fault. Correct any related faults that are shown; see the subject Detected Faults. The related faults are:

CID 0138 - Reduced Rimpull Selector Switch

CID 0678 - Impeller Clutch Solenoid Valve

2. If no related faults are present (or have been corrected); then check the reduced rimpull ON/OFF switch and the reduced rimpull selection switch circuits. Disconnect machine harness connector J1 and J2 from the ECM. At the machine harness connectors for the ECM, check connector J1 contact 34 (reduced rimpull ON/OFF switch) for correct operation (open/+battery, open/grounded and shorts) with the switch in all positions. Refer to the Electrical System Schematic in the machine Service Manual.

* If the circuits work correctly and the problem remains, then the ECM is faulty. Replace the ECM; see the subject ECM Replacement.
* If the circuits work INCORRECTLY, then the machine harness or the switches are faulty. Troubleshoot the machine harness and the reduced rimpull switches. Disconnect the machine harness from the switch. Check the machine harness and the switches for continuity, shorts and open circuits. Refer to the Electrical System Schematic in the machine Service Manual. Repair or replace the faulty component (switch or harness).

NOTE: If the torque converter temperature exceeds its warning value, then the reduced rimpull function is disabled until the temperature drops below the warning temperature.

Reduced Rimpull Setting


Reduced Rimpull Selection Switch
(1) Reduced rimpull selection switch. (2) 85 percent preset rimpull percentage. (3) 70 percent preset rimpull percentage. (4) 55 percent preset rimpull percentage. (5) 45 percent present rimpull percentage.

Service personnel use this mode to program the four preset rimpull control settings. The four rimpull settings on the rimpull selector switch are used to match machine rimpull with job site conditions. This procedure is used to change the value of the four rimpull settings.

This procedure should be used whenever the four rimpull settings need to be adjusted.

1. Turn the key start switch to the ON position.


Front Dash Right Side
(1) Keypad. (2) Message display.

2. Press the [OK] key on keypad (1) repeatedly until all faults and status events have been acknowledged and the hour meter appears on message display (2) of the message center module.

3. On the keypad, enter SERV (7378) and then [OK]. Press the scroll key [>] to scroll through the various calibration modes until the message display reads:

4. The current reduced rimpull settings values will scroll on the message center display until the following appears:

5. If [OK] is pressed, the current reduced rimpull settings will be accepted, and the message display will read:

6. If [>] is pressed, you will be asked to accept/change the rimpull percentage value of the four settings. Press [>] to change the percentage in increments of 5%.

7. Follow the instructions on the message display to complete the procedure.

8. Exit the reduced rimpull setting mode.

NOTE: The procedure forces the settings to be descending order.

Using ET To Set Reduced Rimpull


ET Screen For Transmission 994D Configuration

Procedure:

1. Select "Configuration" from the service menu and the configuration screen is displayed.

2. Select the desired reduced rimpull selection switch setting.

3. Type in the desired new value.

Neutralization Pressure Setting


ET Screen To Change Neutralization Pressure Setting

Service personnel may use the Caterpillar ET service tool to change the neutralization pressure setting. In ET, go to the "Service" icon and select the "Configuration Screen" to change the neutralization pressure. The range of adjustment for the neutralizer pressure switch is 300 kpa (minimum) to 500 kpa (maximum).

The neutralization pressure setting can be changed to match machine conditions to job site conditions. The operator should feel a smooth transition when disengaging the left pedal. When adjustment of the neutralizer function is needed the operator will feel a surge when disengaging the left pedal. Increase the neutralizer pressure slowly until the surge is gone.

Torque Converter Impeller Clutch Solenoid Calibration

This calibration procedure is used to allow the ECM to determine the amount of current required to begin impeller clutch engagement. The ECM uses this information to establish the impeller clutch pedal minimum command value and to determine the impeller clutch direction shift modulation values.

CALIBRATION REASONS - Calibration should be performed:

* When a MID 081-CID 0678 FMI 13 fault is present.
* When the impeller clutch solenoid valve is replaced.
* When the torque converter is repaired or replaced.
* When the ECM is reprogrammed or replaced.
* On a yearly basis to compensate for wear.
* When instructed by this service manual.

Before the calibration procedure begins the following machine conditions must be met:

1. Parking brake must be set (engaged).

2. Start the engine and run at 1650 rpm to 2000 rpm (use throttle lock).

3. Torque converter outlet oil temperature is stable at 80 to 90°C (176 to 194.0°F) to allow the calibration procedure to begin.

4. Torque converter outlet oil temperature must remain between 75 to 95°C (167 to 203.0°F) once the calibration procedure is in progress. The calibration procedure takes approximately 60 seconds to be completed.

5. Transmission must be in neutral.


Front Dash Right Side
(1) Keypad. (2) Message display.

6. Press the [OK] key on keypad (1) repeatedly until all faults and status events have been acknowledged and the hour meter appears on message display (2) of the message center module.

7. On the keypad, enter SERV (7378) and then [OK]. Press the scroll key [>] to scroll through the various calibration modes until the message display reads:

8. Follow the instructions on the message display to complete the procedure.

9. After the calibration has been completed the message display will read:

10. Once the calibration is completed, VIMS will leave the SERV mode.

NOTE: If the message CALIBRATION FAILED appears, press the scroll key [>] to view the reason for the failure. Press the [OK] key to acknowledge the error. Follow the instruction on the display to complete the procedure.

The calibration can not be performed if there is a fault with the converter speed or impeller clutch solenoid valve.

Using ET To Calibrate The Impeller Clutch Solenoid


ET Screen For Impeller Clutch Solenoid Calibration

Procedure:

1. Select the calibration item from the service menu and then the impeller clutch solenoid calibration item. The impeller clutch solenoid calibration screen is displayed.

2. The top window of the screen displays the current values for the parameters involved in the calibration. For this calibration, the parking brake status, engine speed, torque converter oil outlet temperature and gear lever are displayed.

3. The middle window of the screen displays calibration status.

4. Follow the on screen instructions in the lower window to perform the calibration.

Torque Converter Output And Transmission Output Speed Sensor Replacement


Torque Converter Output Speed Sensor
(1) Nose piece.

NOTE: The air gap of the torque converter output speed sensor automatically adjusts itself when properly installed. Try regapping the sensor before replacing.

Prior to replacement of the sensor, ensure that replacement is necessary. Always check that power is available to the sensor; approximately +10 DCV is required between contacts A and B of the machine harness connector for the sensor. Check the connectors for damage.

Procedure

1. Turn the disconnect switch to the OFF position. Disconnect the machine harness connector from the sensor. Remove the sensor.

2. Fully extend nose piece (1) of the new sensor. At the slots in nose piece (1), use a small screwdriver to pry nose piece (1) out until it no longer moves; approximately 6.5 mm (.25 in).

3. Install the new sensor and tighten to 23 ± 4 N·m (17 ± 3 lb ft).

As the sensor is installed, the nose piece contacts the gear face and slides back into the sensor body. After the sensor is fully tightened, the nose piece is at the correct air gap and no adjustments are required.

4. Inspect the sensor connector of the machine harness. Connect the machine harness to the sensor.

ECM Replacement Or Software Upgrade


ET Screen For Transmission 994D Configuration

Prior to software upgrade or replacement of the ECM, ET must be used to view machine and ECM data on the ECM to be upgraded or replaced. The data must be recorded to ensure proper re-entry after the software upgrade or ECM replacement. The following data must be recorded:

Product Identification Number

Equipment Identification

Transmission Serial Number

Torque Converter Serial Number

Transmission Maximum Forward Gear

Transmission Maximum Reverse Gear

Reduced Rimpull Settings

NOTE: The power train ECM must be re-programmed using Caterpillar ET/WinFlash

NOTE: Rarely is the ECM the cause of a fault. Always check that power is available to the ECM; battery voltage is required between contacts 1 and 6 to contacts 2 and 5 of the machine harness connector (J1) for the ECM.

Procedure

1. Turn the key start switch and battery disconnect to the OFF position. Disconnect the machine harness from the ECM.

2. Remove the ECM.

3. Make sure the replacement ECM has the correct part number.

4. Connect the machine harness to the ECM.

5. Install the replacement ECM.

6. Turn the disconnect and key start switches to the ON position.

Glossary

Active
Refers to the status of a fault or service code. When the fault is active, it is currently present.
Alert Indicator
A red indicator lamp associated with the machine monitoring system that notifies the operator of an abnormal condition. An alert indicator alone indicates a Category I warning.
+Battery
+Battery refers to any of the harness wiring which is part of the circuit that connects to the positive battery post.
+V
+V is a constant voltage that is supplied to a component to provide electrical power for its operation. +V is provided by an electronic control module or the battery.
Caterpillar Electronic Technician (ET)
A diagnostic service tool software program for a personal computer (PC).
CID (Component Identifier)
The CID is a four digit diagnostic code that tells which component or system is faulty. For example; The CID for the direction switch is 0623. Fault code information, including the CID, can be viewed on the message center display or with ET.
Clear
Clear refers to removing diagnostic information from the memory of the ECM. Before clearing a fault, it is necessary that the fault is not active.
Component Identifier (CID)
A code used to identify a particular component.
Connector Contact
A connector contact is the component of a harness connector that actually makes the electrical connection. Connector contacts are either pins or sockets.
Detected Fault
A detected fault is a fault that has been identified by the ECM. The fault is recorded and diagnostic information is available.
Diagnostic
Diagnostic refers to the showing, monitoring and/or recording of information other than normal. Diagnostic information is available from the message center.
Display
Display refers to the gauges, indicators or readouts within the VIMS display area.
ECM
ECM is the acronym for electronic control module.
Electronic Control Analyzer Programmer (ECAP)
A Caterpillar Electronic Service Tool used for programming and diagnosing a variety of electronic controls. It is a dedicated computer which is used for servicing some CAT electronic controls.
Fault
A failure of a component of a machine electronic system. Fault Mode Identifier (FMI) - A code used to identify the type of fault and used with an MID and CID.
Flash Programming
A means of re-programming or updating an ECM without the need for physical replacement of the module.
FMI (Failure Mode Identifier)
The FMI is a diagnostic code that tells what type of failure has occurred. For example; voltage above normal, current below normal or abnormal frequency. The FMI is a two digit code. The FMI is shown on the VIMS message center.
Harness Code
The harness code is used to describe the particular interface module that is sending information to the VIMS main module. Harness code is the status (open or ground) of the harness code inputs. Module identification code is the number that is assigned to a particular electronic control module. Each module has a specific harness code and therefore also a specific module identification code.
Jumper
A jumper is a piece of wire used to make an electrical connection during troubleshooting.
Machine Code
The machine code is a two digit number that the VIMS Monitoring System has assigned to a particular harness code for a particular sales model. Each sales model has a specific sales model harness code and therefore also a specific machine code.
MID (Module Identifier)
The MID is a diagnostic code that tells which electronic control module diagnosed the fault. The MID is a two digit code that is shown in the message center display area of VIMS Monitoring System. The MID No. for the power train ECM is 81.
Service Code
A code which describes a condition (sometimes a problem) in an electronic control system. This code is stored in the ECM for the service technician.
Signal
Signal refers to the condition of the ECM inputs. The types of signal:

A ground signal has continuity with frame ground.

An open signal is not connected to frame ground; the voltage level is approximately 5 DCV.

A +battery signal is at the same voltage level as the voltage of the battery; between 25 and 30 DCV.

Signal Wire
The signal wire is the harness wire which connects the sensor or switch to the ECM.
Switch Input
A switch input is any input of the ECM which is expecting a grounded, open or +battery signal.
Supply Voltage
A constant voltage supplied to a component to provide electrical power for its operation. It may be generated by the ECM, or it may be machine battery voltage supplied by the machine wiring.
Undetected Fault
An undetected fault is a fault that exists and is not found by the ECM, but is found by the operator or service person.

Power Train Electronic Control Simplified Schematic

This is a simplified power train electronic control system schematic that is electrically correct but does not show all the possible harness connectors. For an accurate schematic of a particular machine, always see the Electrical System Schematic in the machine Service Manual.

Caterpillar Information System:

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