ELECTRONIC MODULAR CONTROL PANEL (SR-4 GENERATOR MOUNTED) Caterpillar


Troubleshooting

Usage:



Introduction

On the pages that follow is a list of possible problems. Several common problems are covered but these problems are not arranged in any particular sequence.

Before checking the list of problems, check the ECM display for any diagnostic codes that may be shown. These codes will aid in finding the problem (see Diagnostic Code Interpretation).

Identify your particular type of problem from the Problem List, then go directly to that problem. However, when you begin the procedure for that problem, start at Step 1 and follow through the step by step procedure. The steps in a particular problem provide a definite sequence to be followed for a logical, one by one elimination of many variables. These steps are arranged in order from the more probable/easiest to check, to the less probable/more complex to check.

When the cause of the problem is found and corrected, stop the test. Do not continue through the complete procedure just because it is there.

------ WARNING! ------

Do not connect generator to a utility electrical distribution system, unless it is isolated from the system. Electrical feedback into the distribution system can occur and could cause personal injury or death.

Open and secure main distribution system switch or, if the connection is permanent, install a double throw transfer switch to prevent electrical feedback. Some generators are specifically approved by a utility to run in parallel with the distribution system and isolation may not be required. Always check with your utility as to the applicable circumstances.

--------WARNING!------

------ WARNING! ------

When servicing or repairing electric power generation equipment, do the following:

a. Make sure the unit is off-line (disconnected from utility power service and/or other generators), and either locked out or tagged "DO NOT OPERATE".
b. Make sure the generator engine is stopped.
c. Make sure all batteries are disconnected.
d. Make sure all capacitors are discharged.

When power generation equipment must be in operation to make tests and/or adjustments, high voltage and current are present. Make sure the testing equipment is designed for and correctly operated for the high voltage and current tests being made. Improper test equipment may fail and present a high voltage shock hazard to its user.

--------WARNING!------

------ WARNING! ------

When the engine-generator, or any source to which the engine-generator may synchronize to, is operating, voltages up to 600V are present in the control panel.

Do not short these terminals with line voltage to ground with any part of the body or any conductive material. Loss of life or injury could result from electrical shock or injury from molten metal.

--------WARNING!------

Test Instruments

Caterpillar Digital Multimeter (6V7070) - can be used for many of the voltage and resistance checks. Rectifiers can also be checked with the special diode function. For further information on using the digital multimeter, see Special Instruction, Form SEHS7734.

NOTE: See the following WARNING if generator is rated over 600 volts.

------ WARNING! ------

On generators with higher than 600 volts rating, do not used direct-reading test equipment to measure the voltage or line current, (even though the instrument has higher voltage capacity). Voltage and current transformers with a high voltage reading must be used. On power circuits higher than 600 volts, direct reading meters CAN have insulation failure and present a high voltage shock to the user.

--------WARNING!------

Diagnostic Code Interpretation

Diagnostic codes are displayed on the same display as the service hours, engine speed, battery voltage, engine oil pressure, and engine coolant temperature. When a diagnostic code is displayed, the arrow that indicates which of the above parameters are displayed will be missing and a flashing "dIAG" will be displayed. If several faults are present, the diagnostic codes will be displayed in sequence. The diagnostic code can be cleared from display by turning the engine control switch (ECS) to the reset position. Before attempting a repair, move the ECS to the reset position and restart engine to see if problem recurs.

NOTE: See the Problem List for display codes.

Problem List

Problem 1

EMC Display = 01 dIAG, no magnetic speed pickup (speed sensor) signal.

Step 1 (Problem 1)

Test Procedure:

Disconnect speed sensor leads (not ground wires) from terminals 1 and 7 on the ECM and measure resistance with a multimeter. Also measure resistance between speed sensor leads and ground.

Test Results:

1. Resistance between speed sensor leads is between 150 and 270 ohms. Lead to ground resistance is above 5000 ohms.

Speed sensor wiring is okay. Go to Step 2.

2. Resistance is below 150 ohms.

Short circuit in wiring or sensor. Repair wiring or replace speed sensor as needed.

3. Resistance is above 270 ohms.

Wire is broken or connector is defective. Repair broken wire or bad connection or replace speed sensor as needed.

4. Resistance between sensor leads and ground is below 5000 ohms.

Speed sensor is grounded. Repair wiring harness or replace speed sensor as needed.

Step 2 (Problem 1)

Test Procedure:

Reconnect speed sensor leads to terminals 1 and 7 on the ECM. Use a 6V7070 Multimeter (or meter of similar accuracy) to measure AC voltage across terminals 1 and 7 on the ECM while cranking the engine. Be sure that you can reach 250 rpm.

Test Results:

1. Speed sensor voltage is 1.0 volt AC or greater.

Attempt to start. If 01 dIAG reappears, replace speed sensor. If 01 dIAG still appears, replace ECM.

2. Speed sensor voltage is below 1.0 volt AC.

Adjust speed sensor gap (see Service Procedure F). If speed sensor voltage is still low, replace speed sensor.

Problem 2

ECM Display = 02 dIAG, no oil pressure/temperature sensor (transducer) signal.

Step 1 (Problem 2)

Test Procedure:

Measure the voltage between terminal 4 and battery negative of the ECM. Disconnect the 3 pin connector at the press/temp sensor (transducer) and measure the voltage between terminal 4 and battery negative. Disconnect the wire from terminal 4 and measure the voltage between terminal 4 of the ECM and battery negative.

Test Results:

1. Voltage is between 11 and 15 VDC in all cases.

Power supply is okay. Go to Step 2 (Problem 2).

2. Voltage is above 20 VDC in all cases.

Replace ECM. It is likely that press/temp transducer has also been damaged.

3. Voltage is above 15 VDC but below 20 VDC in all cases or below 11 VDC in all cases.

Replace ECM.

4. Voltage goes from below 11 VDC to between 11 and 15VDC when the 3 pin connector is disconnected.

Replace press/temp transducer.

5. Voltage goes from below 11 VDC to between 11 and 15 VDC when wire to terminal 4 is disconnected.

Repair grounded wiring between ECM and press/temp transducer.

6. Voltage is above 15 VDC initially but is between 11 and 15 VDC when wire to terminal 4 is disconnected.

Repair wiring between ECM and press/temp transducer. Wire may be shorted to +24 volts. If so, press/temp transducer will probably fail and should be replaced.

Step 2 (Problem 2)

Test Procedure:

Reconnect any wires that were disconnected in Step 1 (Problem 2). Measure the voltage on terminal 5 of the ECM with respect to battery negative. Use the 6V7070 Digital Multimeter or equivalent meter.

Test Results:

1. Voltage is 4 to 8 VDC.

Go to Step 3 (Problem 2).

2. Voltage is above 8 VDC.

Wire from terminal 5 of ECM to press/temp transducer (sensor) is open or high resistance. Repair as required.

3. Voltage is below 4 VDC.

Recheck supply voltage to the press/temp sensor Step 1 (Problem 2). If OK, disconnect wire to terminal 5 of ECM. If voltage now goes above 8 VDC, replace the press/temp transducer (sensor). If voltage remains low, replace the ECM.

Step 3 (Problem 2)

Test Procedure:

Disconnect the 3 pin connector at the pressure/temperature transducer and measure voltage between battery negative and pin 1 of the wiring harness connector. Also measure resistance between battery negative and pin 2 of this connector.

NOTE: In an emergency situation, it is possible to operate with no oil pressure or coolant temperature protection by reprogramming the ECM (see Service Procedure A). Oil pressure and coolant temperature gages should be installed to give operator an indication of engine conditions. If this is done, be sure to reprogram when the pressure/temperature transducer is replaced.

If the ECM is programmed to operate with no oil pressure and water temperature protection and the 02 dIAG cannot be reset, the ECM is defective. Check for loose connections or low battery voltage before replacing ECM.

Test Results:

1. Voltage is between 11 and 15 VDC and resistance is below 1 ohm.

Supply to press/temp transducer okay. Replace press/temp transducer.

2. Voltage is below 11 VDC.

Repair wiring between ECM and press/temp transducer.

3. Resistance is above 5 ohms.

Repair wiring between ECM and battery negative.

Problem 3

ECM Display = 03 dIAG, a problem with inputs from the ECS.

Test Procedure:

The engine control switch (ECS) must connect ECM terminal 9 or 10 or 11 or 12 to battery negative. If both 9 and 11 are connected to negative, there will be an auto start. Any wiring error or loose connection will cause the 03 diagnostic code. Check ECS and wiring from ECS to ECM repair as needed.

Test Results:

1. Wiring and ECS check OK.

Replace the ECM.

2. Wiring or ECS check bad.

Repair or replace components as necessary.

Problem 4

ECM Display = 04 dIAG, loss of setpoints programmed into the ECM memory.

Test Procedure:

Reprogram the ECM (see Service Procedure A) and turn the ECS to reset.

Test Results:

1. 04 dIAG does not recur.

Problem solved.

2. 04 dIAG recurs.

Replace ECM.

Problem 5

ECM Display = 05 dIAG, engine shutdown with no shutdown command from the ECM.

Step 1 (ETS And Latching Or ETR System) (Problem 5)

Test Procedure:

Crank the engine by moving the ECS to manual position and observe the action of the governor and fuel rack. Also observe the position of the air shutoff (if so equipped). If engine will not crank, troubleshoot starting system according to troubleshooting procedure under Problem 10.

If a 2301 Electric Governor is used, measure the voltage supplied to the governor.

NOTE: See Service Procedure A on how to identify energize to run (ETR) or energize to shutdown (ETS) and latching system.

Test Results:

1. Fuel rack and governor moves in Fuel On direction, and air shutoff lever is in RUN position.

The problem is in the engine or fuel system. Refer to engine portion of the Service Manual.

2. Fuel rack does not move or cannot be observed. Governor may or may not move in Fuel On direction.

Check fuel level. Fill and prime fuel system if level was low. Go to Step 2 (ETS) and latching (Problem 5) or Step 2A (ETR) (Problem 5) if level was low.

3. Air shutoff is in the shutoff position.

Reset air shutoff. Go to Step 4 (Problem 5) if shutoff cannot be reset or if it trips on each attempt to start.

4. 2301 Electric Governor is used and supply voltage is found to be greater than 15 volts.

Problem is in governor or actuator system. Refer to 2301 Electric Governor Service Manual SENR2928.

5. 2301 Electric Governor is used and the supply voltage is found to be less than 15 volts.

Problem is in wiring to the 2301 Electric Governor. Go to Step 3 (Problem 5).

Step 2 (ETS) And Latching (Problem 5)

Test Procedure:

Remove fuse F6 (fuse between terminals R and S) from back of ECM. Be prepared to use manual shutoff if needed. Crank the engine.

Test Results:

1. Engine starts and runs.

The fuel control relay (FCR) is energizing the shutoff or latching solenoid. Check resistance between terminals S and 23. If it is below 5 ohms, go to Procedure B. If not, look for wiring errors that might supply voltage to shutoff solenoid.

2. Engine does not start.

The shutoff solenoid is stuck or the fuel rack is stuck in the shutoff position or solenoid is not correct for the application. Find the source of the problem and correct.

Step 2A (ETR) (Problem 5)

Test Procedure:

Connect a jumper between terminals S and 23 of the terminal strips on the back of the ECM and crank the engine. Be prepared to use manual shutoff if needed.

Test Results:

1. Engine starts and runs.

The fuel control relay (FCR) relay was not energizing the fuel solenoid. Check FCR (see Service Procedure B).

2. Engine does not start.

The fuel solenoid is defective or stuck, or solenoid is not correct, or the fuel rack is stuck in the shutoff position. If there is no voltage at terminal S, fuse F6 may be open and should be replaced. Find the source of the problem and correct.

Step 3 (ETS And Latching Or ETR System) (Problem 5)

Test Procedure

Crank the engine and measure the DC voltage between the following points and battery negative: the battery positive terminal on the preregulator (located under 2301 in control panel), terminal 1 of the F9 fuse if preregulator is not used, terminal 20 on the ECM, terminal M on the ECM and terminal L on the ECM.

Test Results:

1. Voltage is below 15 VDC at all of these points.

Battery voltage is low or wiring from battery to control panel is defective. Charge battery or repair wiring as needed.

2. Voltage is above 15 VDC on terminal L of ECM only. Voltage is low at all other points.

Fuse F4 is blown. Replace fuse.

3. Voltage is above 15 VDC on terminals M and L of the ECM. Voltage is low at all other points.

Run Relay contact is not closing. Check the ECM for diagnostic codes before checking the relay. (See Procedure B.)

4. Voltage is above 15 VDC on terminals M and L and 20 of the ECM. Voltage is low at all other points.

Check the wiring between terminal 20 of the ECM and the battery positive terminal on the preregulator or F9 fuse if preregulator is not used. Repair as needed.

5. All voltages are above 15 VDC. The voltage at the 2301 remains low.

The preregulator fuse or the F9 fuse or the preregulator or wiring is defective. Repair as needed.

Step 4 (Problem 5)

Test Procedure:

Check for another diagnostic code. If none is displayed, remove fuse F7 (between terminals T and U) from back of ECM.

Test Results:

1. Air shutoff does not trip and engine starts.

The air shutoff relay (ASR) is energizing the solenoid. Check resistance between terminals U and 24 on the ECM. If it is below 5 ohms, go to Procedure B. If not, look for wiring errors that might supply voltage to shutoff solenoid.

2. Air shutoff continues to trip.

The air shutoff is defective. See Engine Service Manual section on the air shutoff.

3. Air shutoff does not trip and engine does not start.

Check diagnostic code and return to Step 1 (Problem 5) if code 05 is still displayed.

Problem 6

EMC Display = 06 dIAG, internal failure of ECM or unstable voltage supply.

Test Procedure:

Reset and wait 90 seconds. Restart to see if problem re-occurs. If it does, look for possible sources of electrical noise such as loose connections in supply to ECM. Install jumper between terminals D and F of the ECM. Reset and start engine.

Test Results:

1. 06 dIAG recurs only when engine is running.

Loose connection between battery + or - to ECM is still likely. Run separate supply wires. Replace ECM if this fails to correct problem.

2. 06 dIAG recurs when engine is not running.

Loose connection still possible but less likely. Replace ECM unless an external electrical noise source can be identified.

3. 06 dIAG does not recur.

Check crank termination relay (CTR) or fuel control relay (FCR) contacts or leave jumper connected if battery drain is not a problem.

4. 06 dIAG reoccurs when engine is starting and engine cranks slowly or not at all.

Battery voltage is low. Charge and/or replace batteries.

Problem 7

ECM Display = 07 dIAG, internal ECM programming switch does not match program.

Test Procedure:

The 07 dIAG code simply indicates that the setpoint value programmed into setpoint 02 does not match the position of the rotary switch. (See Procedure A.)

Problem 8

ECM Display = 08 dIAG, temperature probe problem.

Test Procedure:

If ambient temperature is near -40°C (-40°F), use heaters to warm up the engine before startup. If temperature is more reasonable (warmer) check connectors between oil pressure/temperature transducer (sensor) and the temperature probe before going to Service Procedure G.

Problem 9

Engine cranks but does not start or shuts down immediately after starting.

Test Procedure:

Look at the ECM Display.

Test Results:

1. Overcrank LED's is lit (is on).

Reset control and check cycle crank time and overcrank time setpoints (see Service Procedure A). Both times should be 5 seconds or more. If engine will not start in 5 seconds, troubleshoot engine/fuel system/governor.

2. Overcrank LED did not light (if off). If the engine started and then shut down an 05 diagnostic code should be displayed.

Go to Problem 5, diagnostic code 05, regardless if 05 is displayed or not.

3. Some other diagnostic code is displayed.

Go to Problem List and do problem indicated by the diagnostic code.

Problem 10

Engine does not crank.

Step 1 (Problem 10)

Test Procedure:

Look at ECM Display.

Test Results:

1. All 6 LED fault indicators are on.

Go to Problem 12, all six LED fault indicators are on.

2. One or more but not all of the 6 LED fault indicators are flashing.

There is a shutdown fault. Go to Problem List and the problem indicated by fault.

3. A diagnostic code is displayed.

Go to Problem List and do problem indicated by the diagnostic code.

4. No LED fault indicators are lit and no diagnostic code is displayed.

Defect is in the starting circuit. Allow five minutes for CB2 in control panel to cooldown and automatically reset. Attempt to start the engine. If engine will not crank go to Step 2 (Problem 10).

Step 2 (Problem 10)

Test Procedure:

Look at the battery voltage displayed on the ECM Display.

Test Results:

1. Voltage is low (1 to 20 volts).

Charge the battery or repair loose connections between battery cable terminal and battery.

2. Voltage is above 20 volts.

Go to Step 3 (Problem 10).

Step 3 (Problem 10)

Test Procedure:

Prepare for the engine to crank. Momentarily connect a wire between terminals 1 and 5 on the generator mounted terminal strip (TS1).

Test Results:

1. Engine cranks.

Go to Step 4 (Problem 10).

2. Engine does not crank.

Check to see if terminals 4 and 5 on TS1 are jumpered together. If so, the magnetic switch (see Service Procedure E) or the pinion solenoid or the starter motor is defective. Repair or replace as required.

Step 4 (Problem 10)

Test Procedure:

Attempt to start engine (ECS in manual) and measure voltage between ECM terminal 25 and battery negative, terminal W and battery negative, battery positive and battery negative.

Test Results:

1. All voltages are below 20 VDC.

Battery or wiring to ECM is defective. Repair or replace defective parts.

2. Only the voltage on terminal 25 is below 20 VDC.

Check the starter motor relay (SMR) (see procedure B).

3. The voltage on terminals 25 and W are below 20 VDC. The battery position is above 20 VDC.

Replace fuse F8. Also check wiring from terminal W to battery positive.

Problem 11

Starter remains engaged or continues to run after engine has started.

Step 1 (Problem 11)

Test Procedure:

Check for diagnostic codes on the ECM display and go to that respective problem. If no diagnostic codes are shown, shut the engine down and check the voltage between terminals 5 and 2 (5 is positive) on the generator terminal strip (TS1).

Test Results:

1. Engine continues to crank and 15 VDC or more is measured.

Go to Step 2 (Problem 11).

2. Engine no longer cranks.

Check crank terminate setpoint (see Service Procedure A, Engine Setpoint Chart). If setpoint is OK, go to Problem 1 under 01 dIAG. If speed sensor signal is good and shielded wire is in good condition, replace the ECM.

3. Engine continues to crank and there is less than 1 VDC between terminals 5 and 2.

Problem is in magnetic switch (see Service Procedure E) or in starter or pinion solenoid. Repair as required.

Step 2 (Problem 11)

Test Procedure:

Disconnect wire No. 5 on the generator terminal strip TS1.

Test Results:

1. Engine no longer cranks. Voltage between terminals 5 and 2 on generator terminal strip is still above 15 VDC.

Check resistance between terminals W and 25 on ECM. If it is below 5 ohms, go to Service Procedure B. If not, check for shorts or incorrect wiring that supplies voltage to terminal (5).

2. Engine continues to crank.

Problem is in magnetic switch (see service procedure E) or in starter or pinion solenoid. Repair as required.

Problem 12

Engine shutdown occurs, and/or all six LED fault indicators on the ECM are on.

Test Procedure:

Be sure that the control panel lamp test switch (LTS) has not been activated. Disconnect wires from terminal 8 on the ECM. Measure the DC voltage between battery positive and battery negative on ECM.

Test Results:

1. Fault LED's do not turn on.

Test switch (LTS) or wiring is grounded. Correct the problem.

2. Fault LED's continue to be on. Battery voltage is 15 VDC or less.

Battery voltage is low, charge battery or correct wiring problem as required.

3. Fault LED's continue to be on. Battery voltage is above 15 VDC.

Replace the ECM.

Problem 13

LED fault indicator on the ECM will not reset.

Test Procedure:

Move the engine control switch (ECS) to the reset position. If the LED does not go out, connect a jumper wire between terminal 12 on the ECM and battery negative. Disconnect jumper wire.

Test Results:

1. LED resets (goes out) when jumper wire is connected.

Problem is in ECS or wiring to the ECS. Repair as required.

2. LED does not reset (still lit).

Be sure that the fault condition no longer exists. (Example: Engine high coolant temperature LED is lit and engine is cool). If fault cannot be reset, replace the EMC.

Problem 14

Engine shutdown occurs, overcrank LED is lit.

Test Procedure:

Turn ECS to the reset position. If the overcrank LED does not go out, do Problem 13. If the LED goes out, go to Problem 9, "engine cranks but does not start" under test results 1.

Problem 15

Engine shutdown occurs, overspeed LED is lit.

Test Procedure:

Turn ECS to the reset position. If the overspeed LED does not go out, do Problem 13. If the LED goes out, check for possible causes of overspeed. If no causes are found, check the overspeed setpoint according to Service Procedure A. Attempt to start engine by moving the ECS to manual position.

Test Results:

1. Overspeed LED resets and engine starts and runs. Overspeed setpoint is correct.

Hold verify switch on back of the ECM in verify position and increase speed until shutdown occurs. If shutdown speed is 75% of overspeed setpoint, the overspeed function is OK. Look for governor or system problems. If shutdown speed is incorrect, go to Service Procedure F. Replace the ECM if no speed sensor problem is found.

2. Overspeed LED resets and engine starts, but overspeeds again.

If speed goes above overspeed setpoint, repair governor or system problem. If speed does not go high, go to Service Procedure F. Replace the ECM if no speed sensor problem is found.

3. Overspeed setpoint is below specifications.

Program is the correct setpoint according to Service Procedure A.

Problem 16

Engine shutdown occurs, low oil pressure LED is lit.

Test Procedure:

Turn ECS to the reset position. If the low oil pressure LED does not go out, do Problem 13. If the LED goes out check for possible causes of low oil pressure. If no causes are found, check the oil step speed and pressure settings that have been programmed into the ECM (see Service Procedure A).

Start the engine and check engine oil pressure at both low idle and high idle speed using the ECM display and a reliable oil pressure gauge. It may be necessary to program the ECM to operate without oil pressure protection. If the oil pressure is low, do not continue. Shut the engine down and repair the problem in engine lube system.

NOTE: In an emergency situation, it is possible to operate with no oil pressure or coolant temperature protection by reprogramming the ECM (see Service Procedure A). Oil pressure and coolant temperature gages should be installed to give operator an indication of engine conditions. If this is done, be sure to reprogram when the pressure/temperature transducer (sensor) is replaced.

Test Results:

1. Engine oil pressure is below setpoints at low or high idle. See Identification section, character five for specific engine setpoints. Measurements by gauge and ECM display agree.

Problem is in engine. Refer to engine service manual.

2. One or more oil pressures are below the settings programmed into the ECM or oil step speed is set near low idle.

Check the pressure and speed specifications according to the model number identification fifth character. See Identification. If the ECM settings are incorrect, reprogram to correct the settings. If the ECM settings are correct, correct the engine problem. Refer to the engine service manual.

3. Engine oil pressure as measured with a gauge is at or above the ECM settings. Engine oil pressure as measured by ECM display is below the ECM settings.

Check the wiring and oil supply to the pressure/temperature transducer (sensor). If no problem can be found, replace the pressure/temperature transducer.

Problem 17

Engine shutdown occurs, high coolant temperature LED is lit.

Test Procedure:

Turn ECS to the reset position. If the high coolant temperature LED does not go out after engine is cool, do Problem 13. If the LED goes out check for possible causes for high coolant temperature. If no causes are found check the coolant temperature setting that has been programmed into the ECM (see Service Procedure A). It should be set for the specific engine model. See Identification section, character five for specific engine setpoints. Install an accurate coolant temperature gauge with the sensing bulb in area of high coolant flow, as close to temperature probe as possible. See note in Problem 16 under Test Procedures. Start the engine.

Test Results:

1. Coolant temperature setpoint is below proper shutdown setpoint.

Temperature setpoint is not correct. See Service Procedure A.

2. Temperature displayed by ECM and by gauge agree and is above the temperature setpoint. Setpoint is correct and high coolant temperature LED is still lit.

Engine is overheating. Troubleshoot cooling system.

3. Temperature displayed by ECM is 5°C (9°F) or higher than the temperature displayed by the gauge.

Check temperature probe (see Service Procedure G). If it is good, repeat test. Be sure of gauge accuracy. If ECM continues to read high, replace the pressure/temperature transducer (sensor).

4. Temperature displayed by ECM and by gauge agree and are below the temperature setpoint.

Go to Problem 13.

5. Temperature displayed on the ECM is the word "Hi" and the temperature on the gauge is below 98°C (208°F).

Check for shorts in wiring to the pressure/temperature transducer (sensor). Also check the temperature probe (see Procedure G).

Problem 18

Engine shutdown occurs, emergency stop LED's is lit.

Test Procedure:

Reset the emergency stop pushbutton by turning until it pops out. Turn the ECS to "OFF/RESET" position. Disconnect the wire from terminal 14 on the ECM if LED remains on after attempting to reset.

Test Results:

1. Emergency stop LED goes out when wire is disconnected.

Emergency stop switch is stuck closed or grounded or wire is grounded. Repair as required.

2. Emergency stop LED remains on.

Move ECS to reset and back to manual position. If LED remains on, go to Problem 13.

Problem 19

Engine shutdown occurs, optional reverse power relay LED is lit.

Test Procedure:

Turn the ECS to the reset position. If the reverse power LED does not go out, disconnect wire from terminal 13 on the ECM.

Test Results:

1. Reverse power LED goes out (resets) after resetting.

Problem was reverse power fault. Control panel is OK.

2. Reverse power LED goes out when wire is disconnected from terminal 13.

Reverse power relay will not reset. Check wiring and replace reverse power relay as required.

3. Reverse power LED remains lit.

Go to Problem 13.

Problem 20

No engine shutdown when a fault occurs.

Test Procedure:

Look at the ECM Display. If there is a diagnostic code displayed or a fault LED lit and the engine is not shut down, go to Step 1 (ETS and latching) (Problem 20) or Step 1A (ETR) (Problem 20) or Step 1B (3500 engine with 2301 governor) (Problem 20). If there is no diagnostic code or fault displayed, go to Step 2 (Problem 20).

Step 1 (ETS And Latching) (Problem 20)

Test Procedure:

Check the DC voltage relative to battery negative on TS1 terminal 7 in the generator and on terminals 23 and S and R on the ECM. The engine should be running with fault LED lit when checks are made.

Test Results:

1. All voltages are above 20 VDC.

The wire from terminal 7 in generator to solenoid is open or fuel shutoff solenoid is defective or not adjusted correct. Repair as required.

2. Voltage at terminal 7 in generator is below 20 VDC. The other voltages are above 20 VDC.

The wire from terminal 7 in generator to terminal 23 in the ECM is open. Repair wire or connection.

3. Voltage of terminal 23 in ECM and terminal 7 in the generator is below 20 VDC. The other voltages are above 20 VDC.

The FCR relay may be stuck open. Go to Service Procedure B.

4. All voltages are below 20 VDC except for Terminal R on the ECM.

Replace Fuse F6. If problem continues solenoid may be shorted or wiring grounded. Repair as required.

5. All voltages are below 20 VDC.

Connection from battery positive to terminal R is defective. Repair as required.

Step 1A (ETR) (Problem 20)

Test Procedure:

Remove fuse F6.

Test Results:

1. Engine shuts down.

Fuel control relay (FCR) contact is stuck closed. Check resistance between terminals S and 23 on ECM. If it is below 5 ohms, go to Service Procedure B. If not, look for wiring errors that might supply voltage to fuel control solenoid.

2. Engine continues to run.

Fuel control solenoid is stuck in run position. Shut engine down manually and troubleshoot solenoid and linkage.

Step 1B (3500 Engine With 2301 Governor) (Problem 20)

Test Procedure:

Remove Fuse 4.

Test Results:

1. Engine shuts down.

Run relay (RR) contact is stuck closed. Check resistance between terminals M and 20 on ECM. If it is below 5 ohms go to Service Procedure B. If not, look for wiring errors that might supply voltage to 2301 governor.

2. Engine continues to run.

Rack or electric actuator is stuck in fuel on position. Shut engine down manually and troubleshoot governor linkage.

Step 2 (Problem 20)

Test Procedure:

Record all of the readings from the ECM display. Shut engine down and check the setpoint (see Service Procedure A) of the parameter that should be shutting engine down. If readings from the display are within allowed setpoints, there is no problem. If not, replace ECM.

Problem 21

Engine shutdown with no LED's lit or diagnostic codes on ECM.

Test Procedure:

Check to make sure ECM terminal 15 is not receiving a signal to shutdown (connect to battery negative B-).

Test Results:

1. Terminal 15 connected to battery negative (B-).

Problem is in wiring, find defect and repair or replace it.

2. Terminal 15 not connected to battery negative.

If no other defects can be found replace the ECM.

Problem 22

Remote annunciator or control panel alarm module, data link controlled LED's all flash at a rate of once per two seconds (0.5 Hz).

Test Procedure:

Momentarily disconnect the battery or wire 1 at TS1-1 that is used to power the ECM. If the LED's stop flashing after the battery is reconnected, the problem is solved. If the LED's still flash, check to make sure serial data link wire 18 has good continuity from ECM terminal 6 to alarm module terminal 2.

Test Results:

1. No continuity of wire 18.

Repair or replace defective wire.

2. Wire 18 has continuity.

Replace ALM or remote annunciator or ECM.

Problem 23

ACM displays all dashes "---".

Test Procedure:

Disconnect the DC power to the ACM for a moment by turning the ECS to the "OFF/RESET" position. Start and run the engine if the dashes do not go away replace the ACM.

Problem 24

ACM Hz displays "LO" and voltmeter displays "0".

Test Procedure:

Make sure the AVS is not in the "0" position. Check AC volts connections to ACM terminals 1 and 2 to make sure the generator AC voltage is being applied.

Step 1 (Problem 24)

Test Results:

1. Generator AC voltage is measured at terminals 1 and 2.

Go to Step 2 (Problem 24).

2. Generator AC voltage is not measured at terminals 1 and 2.

Check fuses F11, F12, F13 AVS and wiring for defect. Repair or replace any defective part.

Step 2 (Problem 24)

Test Procedure:

With the engine started check the DC voltage connected to ACM terminals 5 and 12 (terminal 12 is positive). The DC voltage must be above 15 volts.

Test Results:

1. DC voltage is below 15 volts.

Check batteries and charging system for cause of low batteries.

2. DC voltage is above 15 volts.

Replace the ACM.

Caterpillar Information System:

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