PEEC - Related OEM Truck System Responsibilities and Troubleshooting Guide{0781, 0782} Caterpillar

Introduction

The testing procedures, in this instruction, provide an inexpensive method to check the integrity of the truck wiring system. Specifically, that part of the truck wiring system which is directly related to the 3406B Programmable Electronic Engine Control (PEEC) Engine.

The procedures can be performed using only a voltmeter and breakout "T"s (adapter cables).

Also, there are two additional areas of PEEC - related truck system responsibility which are not covered by the testing procedures.

Refer to PEEC Truck System Tests Not Covered by the Digital Multimeter, in this instruction.

A section of this instruction, PEEC System Operations, briefly describes operation of a truck with PEEC.

This section also defines the Customer Specified Parameters.

Reference: Special Instructions

SEHS8741 ... Using the 8C5919 PEEC Functions Service Program Module ... and

SEHS8742 ... Using the 8T8697 Electronic Control Analyzer Programmer (ECAP) ... or

SEHS8743 ... Using the 8T5282 Digital Diagnostic Tool (DDT) Group With the 3406B Programmable Electronic Engine Control (PEEC) Module.

Service Manual (Module)

Service Manual (Module) ... SENR3479 ... 3406B (PEEC) Truck Engine Test Procedures

NOTE: These publications are not needed for all portions of the troubleshooting procedures and will ONLY be referenced when required.

Tools Required

NOTE: Refer to REFERENCE, in this instruction, for the related special instructions.

8T8697 Electronic Control Analyzer Programmer (ECAP) ... or

8T5282 Digital Diagnostic Tool (DDT) Group

6V7070 Digital Multimeter, (preferred), or 6V7800 Digital Multimeter (Regular Duty).

8T8726 Adapter Cable Assembly - Three pin breakout "T" (Included with 8T5282 Group).

8T8694 Adapter Cable Assembly - Five pin breakout "T".

8T8695 Adapter Cable Assembly - Nine pin breakout "T".

Wire removal tool - 1U5805 Electrical Connector for 12 - 14 gauge wire or 8T5318 Electrical Connector for 16 - 18 gauge wire.

Contact the OEM for suggested repair procedures to the truck wiring and pins.

Contact a Caterpillar dealer or a TEPS dealer for new connectors.

Test Procedure

1. Interview the driver to determine the details of the problem:

* When the problem occurs ... and/or* Under what conditions.

2. Determine which operational problem exists.

Refer to Operational Problem Chart in this instruction.

3. Check voltages and/or ohms at the connector shown to the right of the existing Operational Problem shown in Operational Problem Chart, in this instruction.

Refer to Location of PEEC Truck System Connectors, in this instruction, to help determine the physical location of the connectors.

4. Correct any error that is found within the truck connectors, pins, wires or switches.

Refer to PEEC System Wiring Schematic in this instruction, to follow current flow.

5. If the problem is not resolved by obtaining the proper voltages and/or ohms at the appropriate connectors:

* The problem may be within the PEEC engine system or* One of the two areas shown in the following section, PEEC Truck System Tests Not Covered by the Digital Multimeter.

NOTE: Further tests will require the use of specified PEEC service tools, Service Program Modules (SPM) and Special Instructions:

Refer to Reference and Tools Required in this instruction.

PEEC Truck System Tests Not Covered by the Digital Multimeter

With the multimeter tests, it is not possible to accurately determine the proper adjustment of the linkages to the throttle position sensor.

It is also not possible, with the multimeter, to determine if a Customer Specified Parameter is causing the problem.

For example, if the Low Cruise Control Speed Set Limit is set at 72 km/h (45 mph), the Cruise Control could NOT be activated below this speed.

This could result in a possible complaint that the Cruise Control does not work.

A more typical value for Low Cruise Control Speed Set Limit is 48 to 56 km/h (30 to 35 mph).

Proper Adjustment of the Throttle Linkages

7T5596 Control Group (Throttle Position Sensor)

The throttle linkages contain mechanical stops to prevent breakage of the rotating wheel on the front of the 7T5596 Throttle Position Sensor.

The low idle stop in the throttle linkages should be adjusted to allow little or no downward motion of the foot pedal before the engine rpm increases (dead pedal motion).

Excessive dead pedal motion is undesirable.

With PEEC, the maximum engine rpm obtainable is the Top Engine RPM Limit (TEL).

The TEL rpm on the 3406B PEEC Engine and high idle rpm on the mechanically governed 3406B are similar.

With PEEC, the TEL rpm in neutral is obtained before the throttle position sensor reaches its maximum signal.

If the TEL throttle linkage stop is set by ear (without instrumentation), PEEC will not obtain full engine horsepower.

NOTE: A DDT or ECAP service tool MUST be used to adjust the TEL throttle linkage mechanical stop.

7X1930 Pedal Position Sensor (Pedal Mounted Sensor)

For engines using the 7X1930 Pedal Mounted Sensor, the calibration of the sensor is done automatically by the Electronic Control Module (ECM).

A DDT or ECAP can be used to display the proper throttle percentage:

Throttle fully released 3%

Throttle fully depressed 100%

NOTE: Further tests will require the use of specified PEEC service tools, Service Program Module (SPM), Special Instructions and Service Manual:

Refer to Reference and Tools Required in this instruction.

Excessive motion past the TEL full power position can damage the rotating disc on the front of the throttle position sensor.

Responsibility for Throttle Pedal Adjustment

NOTE: The Throttle Position Sensor (TPS) is supplied by Caterpillar.

The installation of the TPS and the initial proper adjustment of the throttle pedal linkage mechanical stops are the responsibility of the truck manufacturer (O.E.M).

For more details, see the truck manufacturer's recommendations on the throttle pedal linkage adjustments.

Visual Inspection and Repair of Connectors

The Deutsch connectors used on 3406B PEEC Engines should be visually inspected at the beginning of each connector test.

Further details on the visual inspection are covered in the specific connector test sections in this instruction.

If the pins or sockets on the truck supplied wiring are excessively corroded or damaged and need replacement, contact the truck manufacturer for his repair recommendations.

The Caterpillar 1U5803 Connector Repair Kit can be used to install new pins or sockets on the existing wires or replace a Deutsch connector assembly (plug and/or receptacle).

Location of PEEC Truck System Connectors

Proper Wiring of Vehicle Speed Sensor

A single type winding (single output) is recommended for use as a vehicle speed sensor for the PEEC system.

Experience has shown that the use of a dual type (dual output) vehicle speed sensor can contribute to electrical noise problems.

Refer to PEEC System Wiring Schematic, in this instruction, for the recommended wiring of the vehicle speed sensor, vehicle speed buffer and speedometer.

NOTE: Grounding the vehicle speed buffer and speedometer at the same location is required.

Recommended Wiring for Vehicle Speed Circuit

Field reports have shown problems with wiring in the vehicle speed circuit on 3406B PEEC engines.

Symptoms include:

* Erratic operation of speedometer.* Erratic operation (cutting out) in Cruise Control mode and ... possibly* Fault Code 31 - Vehicle Speed Signal Fault ... or* Fault Code 36 - Vehicle Speed Signal Overrange.

A single type winding magnetic pickup sensor (Caterpillar 6S7772 Sensor or equivalent) is recommended for use as a vehicle speed sensor.

Experience has shown that the use of a dual type (dual output) vehicle speed sensor can contribute to electrical noise problems.

Illustration 1. Single winding vehicle speed sensor. RECOMMENDED.

Most of these problems can be corrected by rewiring the speedometer and vehicle speed buffer, as shown in Illustration 3, using a single winding (single output) vehicle speed sensor.

Illustration 2. Dual winding vehicle speed sensor. NOT RECOMMENDED.

Illustration 3. Single winding vehicle speed sensor. NOT RECOMMENDED.

NOTE: Speedometers that have a differential input should be wired as shown in Illustration 3.

To determine if the speedometer is equipped with a differential input, the resistance, when measured between either lead to the speedometer and ground, will be GREATER than 2000 ohms.

NOTE: Illustrations 2 and 3 show how this circuit may have been wired, using either a dual winding (Illustration 2) or single winding vehicle speed sensor (Illustration 3).

NOTE: It is difficult to detect electrical noise without the use of an oscilloscope.

When problems arise with the vehicle speed circuit, the following steps can be used to reduce diagnosis and/or troubleshooting time.

1. Remove the vehicle speed sensor and inspect the sensor for damage or wear.

Also, the sensor should be free from any metallic debris. Such debris can cause intermittent and/or erratic vehicle speed signals similar to those caused by a faulty connector.

Clear the sensor of any debris before installing.

NOTE: The accumulation of debris on the sensor will occur again if the transmission oil is contaminated with metallic debris.

If the problem with the vehicle speed circuit persists, proceed to Step 2.

2. If the speedometer is receiving its signal directly from a dual winding vehicle speed sensor (Illustration 2):

* Disconnect the two wires from the sensor that go to the speedometer.

3. If the speedometer is receiving its signal from the vehicle speed buffer (Illustration 3):

* Disconnect the two signal wires leading from the vehicle speed buffer to the speedometer.

4. Connect an ECAP or DDT to the P1/J1 connection and road test the vehicle to see if the original conditions still exist.

Refer to Reference and Tools Required in this instruction.

If no FAULT CODE(s) exists:

* Proceed to Rewiring Procedures For a 3406B (PEEC) Truck Engine, in this instruction.

If any FAULT CODE(s) exist:

* Reconnect the speedometer to the speed buffer.* Follow the troubleshooting procedures as shown in SENR3479 3406B (PEEC) Truck Engine Test Procedures.

Rewiring Procedures For a 3406B (PEEC) Truck Engine

Single winding vehicle speed sensor. RECOMMENDED.

1. Remove the ground wire located in PIN B of connector J13.

2. Remove wire E from connector J13 (wire from negative lead on speedometer), and insert the wire into location B of connector J13.

3. Insert 8T8737 Plug (Deutsch connector plug) into location E of connector J13.

NOTE: Certain speedometers have an internal signal (-) to ground connection. If this internal connector is NOT present, an additional external wire should be used to tie these connections together.

Refer to the above illustration.

NOTE: The vehicle speed buffer is designed to operate with commonly used electrical speedometers.

4. If the problem is not resolved after rewiring the circuit in Step 3:

* Reverse the vehicle speed sensor leads and retest.

5. If the problem persists (after the retest):

* The speedometer may need to be repaired or replaced ... or* The speedometer is of the differential voltage type versus zero crossing.

NOTE: If the transmission has two drilled and tapped holes, a second (Caterpillar 6S7772 Sensor or equivalent) speed sensor may be installed.

Having a dedicated speed sensor for PEEC and a separate dedicated sensor for the speedometer will eliminate electrical noise between these two circuits.

Operational Problem Chart

There are no fault codes displayed for faults in the following truck wiring circuits:

* Cruise Control and PTO; receptacle J2 (F, G, H and J wires).* Check engine light; plug P1 (A, B, G and E wires).* 12V power to PEEC; J2 (A and B wires).* Crank line; J2 (C and B wires).

J2 Connector Tests

1. Disconnect plug P2 from receptacle J2.

The locking ring helps identify P2 from J2.

Check the connections for:

Damaged wires and/or pins and corrosion.

Proper height of the pins in the connector .. and

Check to ensure that the wires and pins are tight in the connectors by pulling (slightly) on each wire of each connector (including the breakout "T").

2. Install the 8T8695 Adapter (nine pin breakout "T") between J2 and P2.

Twist the locking rings to secure the connections.

3. Connect the multimeter as shown.

Measure for the specified voltages between the lettered "T" pins as explained in Steps 4 thru 12.

4. PIN A (+) to PIN B (ground) system voltage should be approximately 12 volts DC with the key ON (no accessories).

Minimum voltage is 11.0 volts DC.

While cranking, the voltage will be between 8 - 12 volts DC.

Diagnosis - Refer to the PEEC System Wiring Schematic, in this instruction, and check wires A and B and connections from J2 through the truck wiring harness back to the battery for the specified voltage.

5. If the voltage check between PIN A and B is LESS than 11.0 volts with the key ON:

Measure the voltage drop from PIN B to the negative battery post while cranking.

NOTE: For this test, the common lead (black) should be connected to the negative battery post first.

Place the positive (red) lead into PIN B. (PIN B is chassis ground.)

Voltage should be LESS than 0.5 volts DC when cranking.

Diagnosis - If the voltage drop is GREATER than 0.5 volts DC:

Check wire B and connections from J2 back to the battery.

Load test battery for adequate electrical energy.

6. PIN C to PIN B:

6 - 12 volts DC while cranking.

Diagnosis - If LESS than 6 volts:

Check wire C and connections from J2 back to the battery.

Load test battery for adequate electrical energy.

Vehicle Speed Buffer (1). Magnetic Pickup (2) in transmission.

NOTE: Step 7 checks the proper functioning of the truck wiring, vehicle speed buffer and vehicle speed sensor.

If a road test is performed, while using an ECAP or DDT, NO further testing in Step 7 is required if the proper VEHICLE SPEED is displayed.

Refer to Reference and Tools Required in this instruction.

NOTE: If the voltages are correct in both parts of Step 7, check the vehicle speed sensor per manufacture's specification.

7. PIN D to PIN B (static check):

Disconnect the magnetic pickup (in transmission) from the input wires of the vehicle speed buffer.

Voltage should be 5 - 7 volts DC with the key ON.

Vehicle Speed Buffer with Jumper Wire

With the jumper wire installed to the speed buffer input wires as shown, voltage is LESS than 0.5 volts DC with the key ON.

Diagnosis - If the voltages are correct in both parts of Step 7, if the voltage is 5 - 7 volts DC and does NOT change when the input wires are opened or jumped:

Remove breakout "T" and check wire from J2 PIN D to J13 PIN D for ground or open.

Remove the jumper wire and reconnect the magnetic pickup to vehicle speed buffer.

Proceed to J13 connector tests.

8. PIN E to PIN B:

LESS than 1.0 volt DC with key ON and foot pedal in low idle position.

GREATER than 3.5 volts DC with foot pedal in high idle position.

Diagnosis - Disconnect breakout "T".

Refer to the PEEC System Wiring Schematic, in this instruction, and check wire E for continuity from J2 PIN E to J12 PIN C:

Also check that wire E is not grounded to the chassis.

Check for open or poor connections.

Proceed to J12 connector tests.

NOTE: Steps 9, 10, 11, and 12 can be more easily checked using the appropriate status screens of an ECAP or DDT.

Refer to Reference and Tools Required in this instruction.

9. PIN F to PIN B:

LESS than 0.25 volts DC with the Cruise Control switch in the ON position and the key ON.

GREATER than 4.75 volts DC with the Cruise Control switch in the OFF position and the key ON.

Diagnosis - Disconnect breakout "T" and check the individual switch circuits for open, ground or faulty switch.

Switch circuit must have LESS than 2.5 ohms resistance.

10. PIN G to PIN B:

LESS than 0.25 volts DC with the key ON.

GREATER than 4.75 volts DC with the brake or clutch activated and the key ON.

NOTE: On some trucks the Cruise Control switch must be in the ON position for this test to work correctly.

Diagnosis - Disconnect breakout "T" and check the individual switch circuits for open, ground or faulty switch.

Switch circuit must have LESS than 2.5 ohms resistance.

11. PIN H to PIN B:

LESS than 0.25 volts DC in RESUME (dec.) position with the key ON.

GREATER than 4.75 volts DC with SET/RESUME switch in the center position and the key ON.

Diagnosis - Disconnect breakout "T" and check the individual switch circuits for open, ground or bad switch.

Switch circuit must have LESS than 2.5 ohms resistance.

12. PIN J to PIN B:

LESS than 0.25 volts DC in SET (accel.) position with the key ON.

GREATER than 4.75 volts DC with SET/RESUME switch in the center position and the key ON.

Diagnosis - Disconnect breakout "T" and check the individual switch circuits for open, ground or faulty switch.

Switch circuit must have LESS than 2.5 ohms resistance.

13. Disconnect breakout "T" and reconnect P2 to J2.

Secure the locking ring.

If problem has not been resolved, proceed to the next connector to be tested as shown in Operational Problem Chart in this instruction.

If this is the last connector to be checked for the operational problem being investigated:

* The problem could lie within the Customer Specified Parameters.

NOTE: the Customer Specified Parameters can ONLY be checked by using a 8T8697 Electronic Control Analyzer Programmer (ECAP) or 8T5282 Digital Diagnostic Tool (DDT) Group.

Refer to Reference and Tools Required in this instruction.

* Review connector tests AGAIN.

J12 Connector Tests

1. Disconnect plug P12 from receptacle J12.

The locking ring helps identify P12 from J12.

Check the connections for damaged wires or pins and corrosion.

Also check that the pins are at the proper height in the connector.

Check that the wires and pins are tight in the connectors by pulling (slightly) on each wire of each connector (including the breakout "T").

2. Install 8T8726 Adapter (three pin breakout "T") between J12 and P12. Twist the locking rings to secure the connections.

3. Connect the voltmeter as shown.

Check for the appropriate voltages between the lettered "T" pins as explained in Steps 4 through 6.

4. PIN A (+) to PIN B (ground) system voltage should be approximately 12 volts DC with key ON (no accessories).

Minimum voltage is 11.0 volts DC.

While cranking, the voltage will be between 8 - 12 volts DC.

Diagnosis - Using the truck wiring schematic, check wires A and B and connections from J12 through the truck wiring harness back to the battery for proper voltage.

5. If the voltage check between PIN A and B is LESS than 11.0 volts with the key ON, check the voltage drop from PIN B to the negative battery post while cranking.

For this test, the common lead (black) should be connected to the negative battery post first.

Then place the positive (red) lead into PIN B. (PIN B is chassis ground.)

Voltage should be LESS than 0.5 volts DC when cranking.

Diagnosis - If the voltage drop is GREATER than 0.5 volts DC, check wire B and connections (including the battery post connections) from J12 to battery negative.

Follow the truck wiring schematic to trace the electrical path from J12 to chassis ground.

NOTE: Step 6 checks the proper functioning of the truck wiring, vehicle speed buffer and vehicle speed sensor.

If a road test is performed, while using an ECAP or DDT, NO further testing in Step 6 is required if the proper VEHICLE SPEED is displayed.

Refer to Reference and Tools Required in this instruction.

6. PIN C to PIN B:

LESS than 1.0 volt DC with the key ON and the foot pedal in the low idle position.

GREATER than 3.5 volts DC with the foot pedal in the high idle position.

Diagnosis - If PIN A to PIN B voltage is proper and the voltage from PIN C to PIN B does NOT vary from low idle to high idle:

Check J12 PIN C and socket connection.

Check for broken throttle linkage from foot pedal to throttle position sensor.

Throttle position sensor needs adjustment or replacement.

NOTE: The Throttle Position Sensor (TPS) is supplied by Caterpillar.

The installation of the TPS and the initial proper adjustment of the throttle pedal linkage mechanical stops are the responsibility of the truck manufacturer (O.E.M).

7. Disconnect breakout "T" and reconnect P12 to J12. Secure the locking ring.

If problem has not been resolved, proceed to the next connector to be tested as shown in Operational Problem Chart in this instruction.

If this is the last connector to be checked for the operational problem being investigated:

* The problem could lie within the Customer Specified Parameters.

Check adjustments of throttle linkage for proper TEL.

NOTE: the Customer Specified Parameters and TEL can ONLY be checked by using a 8T8697 Electronic Control Analyzer Programmer (ECAP) or 8T5282 Digital Diagnostic Tool (DDT) Group.

Refer to Reference and Tools Required in this instruction.

* Review connector test AGAIN.

J13 Connector Tests

1. Disconnect plug P13 from receptacle J13. The locking ring helps identify P13 from J13.

Check the connections for damaged wires or pins and corrosion.

Also check that the pins are at the proper height in the connector.

Check that the wires and pins are tight in the connectors by pulling (slightly) on each wire of each connector (including the breakout "T").

2. Install 8T8694 Adapter (five pin breakout "T") between J13 and P13. Twist the locking rings to secure the connections.

3. Connect the multimeter as shown.

Check for the appropriate voltages between the lettered "T" pins as explained in Steps 4 through 7.

4. PIN A (+) to PIN B (ground) system voltage should be approximately 12 volts DC with key ON (no accessories).

Minimum voltage is 11.0 volts DC.

While cranking, the voltage will be between 8 - 12 volts DC.

Diagnosis - Using the truck wiring schematic, check wires A and B and connections from J13 through the truck wiring harness back to the battery for proper voltage.

5. If the voltage check between PIN A and B is LESS than 11.0 volts with the key ON, check the voltage drop from PIN B to the negative battery post while cranking.

For this test, the common lead (black) should be connected to the negative battery post first.

Then place the positive (red) lead into PIN B. (PIN B is chassis ground.)

Voltage should be LESS than 0.5 volts DC when cranking.

Diagnosis - If the voltage drop is GREATER than 0.5 volts DC, check wire B and connections (including the battery post connections) from J13 to battery negative.

Follow the truck wiring schematic to trace the electrical path from J13 to chassis ground.

NOTE: Step 6 checks the proper functioning of the truck wiring, vehicle speed buffer and vehicle speed sensor.

If a road test is performed, while using an ECAP or DDT, NO further testing in Step 6 is required if the proper VEHICLE SPEED is displayed.

Refer to Reference and Tools Required in this instruction.

6. PIN C to PIN B:

0 volts when stopped.

Up to 2.3 volts DC with the transmission output shaft turning and the speedometer disconnected (open circuit).

NOTE: Not all speedometers are connected to the vehicle speed sensor for their input signal. Some speedometers receive their input from the speed buffer.

Check your truck wiring schematic to determine the electrical path of the speedometer input.

Diagnosis:

Remove magnetic pickup (vehicle speed sensor) from transmission.

If pickup has collected significant metal debris, wipe it clean and install to proper depth.

REPEAT Step 6.

NOTE: The problem may reappear if transmission fluid is contaminated.

Change transmission fluid if necessary.

Check wires and connectors for damage or corrosion from the magnetic pickup to vehicle speed buffer.

Replace vehicle speed buffer, Caterpillar supplied part.

Vehicle Speed Buffer (1). Magnetic Pickup (2) in transmission.

7. PIN D to PIN B (static check):

Disconnect the magnetic pickup (in transmission) from the input wires of the vehicle speed buffer.

With the key ON, the voltage should be 5 - 7 volts DC.

Diagnosis - If the voltage at PIN D is LESS than 0.5 volts DC, go to the next part of Step 7.

Remove P13 from the "T", J13 must stay connected.

Measure the DC voltage of PIN D of the "T" with respect to PIN B:

Voltage at PIN D is 5 - 7 volts DC with the key ON.

Diagnosis - Replace the vehicle speed buffer, Caterpillar supplied part.

Voltage at PIN D is LESS than 5 Volts DC with the key ON.

Diagnosis - Check wire D for ground or open between J13 PIN D to J2 PIN D.

If no ground or open is found, the fault may be in the Electronic Control Module (ECM), a Caterpillar supplied part.

Follow Fault Code 31 or refer to SENR3479 3406B (PEEC) Truck Engine Test Procedures, Test Procedure 112.

8. Disconnect breakout "T" and reconnect P13 to J13. Secure the locking ring.

If problem has not been resolved, proceed to the next connector to be tested as shown in Operational Problem Chart in this instruction.

If this is the last connector to be checked for the operational problem being investigated:

The problem could lie within the Customer Specified Parameters.

NOTE: The Customer Specified Parameters can ONLY be checked by using an 8T8697 Electronic Control Analyzer Programmer (ECAP) or 8T5282 Digital Diagnostic Tool (DDT) Group.

Refer to Reference and Tools Required in this instruction.

Review connector tests AGAIN.

P1 Connector Tests

1. Disconnect plug P1 from receptacle J1. The locking ring helps identify P1 from J1.

Check the connections for damaged wires or pins and corrosion.

Also check that the pins are at the proper height in the connector.

Check that the wires and pins are tight in the connectors by pulling (slightly) on each wire of each connector (including the breakout "T").

2. Install 8T8695 Adapter (nine pin breakout "T") between J1 and P1. Twist the locking rings to secure the connections.

3. Connect the multimeter as shown. Check for the appropriate voltages between the lettered "T" pins as explained in Steps 4 through 8.

4. PIN A (+) to PIN B (ground) system voltage should be approximately 12 volts DC with key ON (no accessories).

Minimum voltage is 11.0 volts DC.

While cranking the voltage will be between 8 - 12 volts DC.

Diagnosis - Using the truck wiring schematic, check wires A and B and connections from J2 through the truck wiring harness back to the battery for proper voltage.

5. If the voltage check between PIN A and B on P1 is LESS than 11.0 volts with the key ON, check the voltage drop from PIN B of the J2 connector to the negative battery post while cranking.

Refer to J2 Connector Tests, Step 5, in this instruction.

For this test, the common lead (black) should be connected to the negative battery post first.

Then place the positive (red) lead into PIN B. (PIN B is chassis ground.)

Voltage should be LESS than 0.5 volts DC when cranking.

Diagnosis - If voltage drop is GREATER than 0.5 volts DC, check wire B and connections (including the battery post connections) from J2 to battery negative.

6. PIN G to PIN B:

2 - 3 volts DC with the key ON, the check engine light ON and the engine NOT running.

12 volts DC with the engine running and the check engine light OFF.

Diagnosis - If check engine light does not work properly, check bulb, fuses and wire G circuitry from P1 PIN G through the check engine light back to the battery.

7. PIN E to PIN B:

NOTE: Some trucks have a push button (momentary) switch to determine engine fault codes.

If so equipped, perform the following two tests:

5 volts DC with the key ON and the switch NOT activated.

0 volts DC with the key ON and the switch activated.

Diagnosis:

Check wiring from PIN E of J1 through push button (momentary) switch to ground for open or poor connection.

Switch circuit from PIN E of J1 to chassis ground must have LESS than 2.5 ohms resistance.

8. PIN H to PIN J:

PEEC data link to electronic dash.

Code 34 and 46 will flash when engine is NOT running. This is normal since no engine speed signal (34) or oil pressure (46) is present when the key is ON but the engine is NOT running.

NOTE: On engines equipped with permanent fault logging personality modules. ONLY Code 34 is displayed when the key is in the OFF position but the engine is NOT running.

Code 46 is no longer displayed at this time.

If the engine has NOT been started, the check engine light will:

Turn ON for five seconds ...

Blink OFF for 0.1 of a second ...

Turn ON for five seconds and then ...

Flash out (display) the faults logged in permanent memory.

9. PIN D to PIN B:

Perform this test with the truck in gear and the engine NOT running.

LESS than 0.25 volts DC with the key ON.

GREATER than 4.5 volts DC with the parking brake activated and the key ON.

Diagnosis - Disconnect the breakout "T" and check the switch circuit for open, ground or faulty switch.

Switch circuit must have LESS than 2.5 ohms resistance.

10. Disconnect breakout "T" and reconnect P1 to J1.

Secure locking ring.

Refer to truck wiring schematic for additional connections at P1.

PEEC System Operations

Starting the Engine

1. Place the transmission in NEUTRAL and depress the clutch to remove the transmission drag and prevent movement of the truck.

NOTE: Depressing the clutch in cold weather can mean the difference between starting and not starting.

Depressing the clutch in warm weather produces faster starts and reduces battery drain.

2. Turn the ignition switch to the ON position and push the crank button or turn the ignition switch to the CRANK position.

NOTE: DO NOT PUSH DOWN OR HOLD THE THROTTLE DOWN until the Check Engine light is OFF.

The PEEC system will automatically provide the correct amount of fuel to start the engine.

NOTE: The PEEC equipped engine may need to crank slightly longer than a mechanically governed engine, because some oil pressure is required for the electronic actuator to move the rack.

The check engine light should be ON while the engine is cranking, but should go OFF, after engine oil pressure is achieved.

At temperatures below 0°C (32°F), it may be necessary to spray starting fluid into the air cleaner inlet.

If the engine fails to start in 30 seconds, release the starter switch and allow the starter motor to cool for two minutes before using it again.

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When using starting fluid, follow the manufacturer's instructions carefully. Use ether sparingly and spray it only while cranking the engine. Also, do not store starting fluid containers in the cab. Failure to do so, could result in an explosion and/or fire and possible personal injury.

3. Do NOT apply load to the engine or increase engine speed until the oil pressure gauge indicates normal. (Oil pressure should raise within 15 seconds after the engine starts.)

Cold Mode Operation

The PEEC system automatically idles the engine at 900 to 1000 rpm for the correct warm up time after a cold engine start [approximately less than 5°C (40°F)].

The PEEC system periodically checks the engine response and will reduce the idle speed to low idle when the engine is warm enough to drive the truck.

The time needed for the engine to reach the normal mode of operation is usually less than the time taken for a walk - around - inspection of the vehicle.

After the engine is started and the cold mode operation is completed, the truck can be operated at low rpm and low power.

The engine will reach normal operating temperature faster when driven at low rpm and low power demand than when idled at no load.

Typically the engine should be up to operating temperature by just driving through the yard toward the open road.

Starting With Jumper Cables

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Batteries give off flammable fumes that can explode. Prevent sparks near the batteries. They could cause vapors to explode. Do not allow jumper cable ends to contact each other or the engine. Improper jumper cable connections can cause an explosion resulting in personal injury. Do not smoke when observing the battery electrolyte levels. Electrolyte is an acid and can cause personal injury if it contacts skin or eyes. Always wear protective glasses when working with batteries.

Engines installed without an engine-to-frame ground strap can be damaged by electrical discharge.

To prevent electrical discharge damage, check to make sure the engine's electrical system has an engine-to-frame ground strap.

For engines which have the alternator connected to an engine component, the ground strap must connect that component to the frame.

Some engines have starter-to-frame ground straps.

But, many of these starters are not electrically grounded to the engine, they have electrical insulation systems.

For this reason, the starter-to-frame ground strap may not be an acceptable engine ground.

1. Connect one end of the cable to the POSITIVE (+) terminal of the battery being started.

Connect the other end to the POSITIVE (+) terminal of the power source.

2. Connect one end of the other cable to the NEGATIVE (-) terminal of the power source.

Connect the other end to the starter NEGATIVE (-) terminal or to the engine block.

This prevents potential sparks from igniting combustible gases produced by some batteries.

3. Start the engine.

4. After the engine starts, disconnect the cable from the starter NEGATIVE (-) terminal or engine block.

Disconnect the other end from the NEGATIVE (-) terminal of the power source.

5. Disconnect the cable from the POSITIVE (+) terminal of the battery on the engine being started.

Disconnect the cable from the POSITIVE (+) terminal of the power source.

Shutoff Solenoid Override

A manual SHUTOFF solenoid override lever is located on the side of the fuel pump.

The engine can be SHUT OFF by rotating the manual shutoff lever in the counterclockwise (CCW) direction.

Rotating the manual shutoff lever in the clockwise (CW) direction disables the shutoff solenoid.

If the solenoid has been disabled, the engine cannot be shut OFF from inside the cab.

The engine can be shut OFF by using the manual shutoff lever on the side of the fuel pump.

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DO NOT operate the engine without the rack actuator solenoid (BTM) in place and with the fuel shutoff solenoid disabled. Excessive engine speed may result.

Customer Specified Parameters

The PEEC system is capable of being programmed for several Customer Specified Parameters.

These parameters are generally programmed so the vehicle will achieve optimum fuel efficiency and operator convenience.

These parameters and a brief explanation of each are as follows:

Engine Power Rating - The 3406B PEEC engines are designed to provide full rated kW (hp) over a large range of engine speeds.

For example, the 1987 Caterpillar 3406B PEEC Truck Engine ratings for the 213 to 231kW (285 to 310 hp) Family are:

Vehicle Identification Number - The owner's description, or unit number of the vehicle.

PTO Vehicle Speed Limit (PTO VSL) - Maximum vehicle speed at which the PTO Governor will function.

PTO Engine RPM Limit (PTO RPM) - Maximum engine rpm attainable using the Cruise Control switches while the vehicle is operated below the PTO VSL (generally used for maximum rpm limit for overnight idling).

Low Gears #1 RPM Limit (LoGr #1) - The rpm at which the engine is limited in the lowest gears.

Low Gears #2 RPM Limit (LoGr #2) - The rpm at which the engine is limited in a secondary gear range.

Low Gears Turn Off Speed (LoGr Off Limits) - The vehicle speeds at which LoGr #1 and LoGr #2 turn off.

Engine RPM at Vehicle Speed Limit (Eng RPM at VSL) - The engine rpm achieved in high (top) gear at VSL. Interruption of the vehicle speed input to PEEC will limit engine rpm to this value at all vehicle speeds.

High Gears RPM Limit (HiGr RPM) - The rpm at which the engine is limited in the higher gears (generally used to encourage shifting into higher gears).

Top Engine Limit (TEL) - Maximum allowable engine rpm generally set at rated rpm [rpm at which maximum kW (hp) is developed, plus (+) 20 rpm].

Vehicle Speed Limit (VSL) - Maximum vehicle speed.

High Gear Turn On Speed (HiGr On) - The vehicle speed above which High Gear RPM is in effect.

Low Cruise Control Set Limit (LCC) - Minimum vehicle speed at which Cruise Control will function.

High Cruise Control Speed Set Limit (HCC) - Maximum vehicle speed in Cruise Control.

Idle Timer Shutdown - Programmable (3 - 60 minutes, in 1 minute increments) before shutdown.

Low Idle RPM - 600 to 750 rpm in 1 rpm increments.

NOTE: The Customer Specified Parameters may be secured by customer passwords.

Your PEEC engine may have all parameters programmed or any combination of parameters programmed.

Operating the Engine

The 3406B PEEC governor functions like the mechanical governor in the mid speed operating range.

There is some droop to provide good driver feel.

The PEEC governor has a programmable low idle speed between 600 and 750 rpm, regardless of load.

This low idle feature makes it easier to start a loaded truck on a steep grade.

The PEEC governor eliminates most of the overrun at high idle that is experienced with a mechanical governor.

Proper operation and maintenance are key factors in obtaining the maximum life and economy of Caterpillar truck engines.

Following the directions in this instruction will lower operating costs.

Operate the engine at low load.

After normal oil pressure is reached and the coolant temperature gauge indicator begins to move, the engine may be operated at full load.

To set the vehicle in motion:

1. Select a gear that will result in a smooth, easy start without increasing engine speed above low idle or slipping the clutch.

2. Engage the clutch SMOOTHLY to prevent excessive stress on the drive train and wasted fuel.

NOTE: It is not necessary to advance the throttle to get the PEEC equipped truck moving from a stop in most instances.

3. Use progressive shifting to reduce fuel consumption.

NOTE: Progressive shifting is using only the rpm required to make an upshift into the next gear.

The amount of rpm required to make an upshift increases as the truck speed increases or if upshifts are made on upgrades.

Experience with your truck will show you how much rpm is required to make upshifts under various conditions.

NOTE: Your PEEC engine may be programmed for Low and High Gears RPM Limiting (progressive shift control).

If the truck can be operated in a higher gear after the desired speed is reached, select the highest gear available that will pull the load.

By following this recommendation, you will lower your fuel costs, since your engine will be operating at the lowest rpm required to pull the load.

NOTE: Your PEEC engine may be programmed so that Vehicle Speed Limit cannot be achieved in LESS than high gear.

Upgrade Operation

On upgrades, begin downshifting when the engine rpm starts to approach peak torque speed.

Fuel economy will be best if you let the engine lug back to around this speed before you downshift.

Downshift until a gear is reached in which the engine will pull the load.

Allow the engine to lug down if you can make it to the top of a hill without downshifting.

Downgrade Operation

On a downgrade, do NOT coast or put the transmission in NEUTRAL.

Select the correct gear that does not allow the engine rpm to go more than 2300 rpm and use the BrakeSaver and/or brakes to limit the speed of the truck.

A simple rule to follow is to select the same gear that would be required to go up the grade.

Programmable Features

The PEEC engine has the programmable features of:

Cruise ControlPTO GoverningVehicle Speed LimitingTop Engine RPM LimitingHigh Gears RPM Limiting ... andLow Gears RPM Limiting included in its functions.

NOTE: The 1988 model year engines, effective with serial number 8TC01413, have Low Idle programming capability from 600 rpm to 750 rpm in 1 rpm increments.

Cruise Control

Cruise control reduces driver fatigue and improves vehicle ride by eliminating throttle bounce.

Cruise control can also reduce fuel consumption and driver to driver variations in a large fleet.

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1. Vehicle speed MUST be ABOVE the low Cruise Control Speed Set Limit, [typically 48 km/h (30 mph)].

2. Set the ON/OFF switch to the ON position.

3. Bring vehicle up to desired road speed.

4. Place the SET/RESUME switch momentarily into the SET position.

The PEEC system will maintain the speed that the truck is traveling when the SET switch is released.

NOTE: If the SET switch is held for more than one (1) second, the truck speed will continue to increase until the SET switch is released.

The cruise speed will then be set to the speed the truck is traveling when the SET switch is released.

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1. Move the ON/OFF switch to the OFF position ... or

2. Depress the clutch ... or

3. Depress the brake.

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1. Return the ON/OFF switch to the ON position.

2. Place the SET/RESUME switch momentarily into the RESUME position.

NOTE: The PEEC system remembers the last Cruise Control SET speed as long as the engine is running.

If the RESUME switch is held for more than one (1) second, the PEEC system will decrease the truck speed and a new SET speed will be established when the Resume switch is released.

The throttle can be used to exceed the Cruise Control SET speed, if the high cruise limit is lower than the vehicle speed limit.

Releasing the throttle will return the truck to the previous cruise speed. The throttle override can be used to anticipate hills or for passing situations.

To shift gears, the ON/OFF switch can be moved to the OFF position or disengage the clutch to deactivate the Cruise Control.

After shifting gears, the Cruise Control can be reactivated by moving the ON/OFF switch to the ON position and momentarily setting the SET/RESUME switch in the RESUME position.

NOTE: The PEEC control system remembers the last Cruise Control SET speed as long as the engine is running.

The PEEC system may have a maximum cruise speed which has been specified by the owner/operator of the truck.

The Cruise Control will only function between a minimum of 48 km/h (30 mph), unless otherwise programmed, and a programmed high cruise speed limit.

The high cruise speed limit is also generally set at a lower km/h (mph) than the vehicle speed limit.

PTO Governor Mode

The Cruise Control function of the PEEC system works as a:

PTO governor ... or

Engine speed governor when the vehicle is stationary ... or

When operated at a vehicle speed below the PTO Vehicle Speed Limit (PTO VSL).

Activation and deactivation of the PTO governor is the same as the Cruise Control.

The PTO governor will operate at any engine speed from low idle to the maximum PTO limit speed which is usually less than rated engine speed.

The maximum PTO governor speed is a Customer Specified Parameter.

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1. To operate the PTO governor, set the ON/OFF switch to the ON position.

The throttle can than be used to determine the desired engine speed.

2. When the desired engine speed is reached, place the SET/RESUME switch to the SET position and release the switch.

The engine speed will be maintained at this set rpm by the PEEC system.

NOTE: If the SET switch is held for more than one (1) second, the PEEC system will increase engine speed until the SET switch is released (up to the PTO Engine RPM Limit, if programmed, or to TEL).

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1. Place the ON/OFF switch in the OFF position ... or

2. Depress the clutch ... or

3. Depress the brake.

028

1. Place the ON/OFF switch to the ON position.

2. Move the SET/RESUME switch momentarily to the RESUME position.

NOTE: If the RESUME switch is held for more than one (1) second:

The PEEC system will decrease engine speed until the switch is released ... and

A new SET speed will then be established when the RESUME switch is released.

Vehicle Speed Limit (VSL)

The 3406B PEEC engine is capable of limiting vehicle speed.

The Vehicle Speed Limit is a Customer Specified Parameter.

The PEEC system will NOT apply any engine power when the vehicle speed is above the Vehicle Speed Limit.

The Vehicle Speed Limit is generally set a few km/h (mph) above the high Cruise Control SET speed.

The purpose of the vehicle speed limiter is to reduce fuel consumption by limiting top vehicle speed.

Higher truck speeds require higher kW (hp), which consumes more fuel.

Top Engine RPM Limit

The PEEC engine also has a customer specified Top Engine RPM Limit (TEL), which may be:

Set as much as 79 rpm LOWER than the maximum engine rated rpm ... or

20 rpm HIGHER than the maximum engine rated rpm.

The PEEC engine is designed to provide rated kW (hp) over a large range of engine rpm's so that full engine power capability is achieved even at lower engine rpm's.

The purpose of the top engine rpm limiter is to eliminate engine operation at high rpm's which results in less fuel being consumed.

Low and High Gears Engine RPM Limiting

To obtain the best fuel economy, the PEEC engine may also be programmed to limit engine rpm at different vehicle speeds to promote shifting to a higher gear.

Up to three different engine rpm limits less than the top engine limit (TEL) for three different vehicle speed ranges can be programmed.

Two low gears rpm limits can be set to promote progressive shifting thru the lower ratios.

A High Gears Engine RPM Limit can also be programmed to promote shifting to the highest gear, eliminating the possibility of operating the engine at the Vehicle Speed Limit in other than the highest gear.

The low gears limiting feature significantly limits the rate of engine acceleration while the truck is in gear and the engine rpm is GREATER than the programmed rpm limits.

The high gear limiting feature is a distinct engine rpm limit when vehicle speed is ABOVE the programmed value.

The Top Engine RPM Limit can be achieved when the vehicle is NOT in gear to assist downshifting.

In the example shown above, the engine will accelerate with full power up to the Low Gears #1 RPM Limit (L.G.#1, 1400 rpm), in the first three gears as defined by the Low Gears #1 Turn Off Speed 19 km/h (12 mph).

If the driver really needs to obtain a higher engine rpm to be able to shift to the next higher gear, the PEEC system will allow the engine to accelerate slowly up to the Top Engine RPM Limit while the vehicle is in gear.

The top engine limit can be achieved when the vehicle is NOT in gear to allow downshifting.

Full engine power can be achieved after downshifting if needed on steep grades.

When the vehicle speed is:

* GREATER than the Low Gears #1 RPM Turn Off Speed 19 km/h (12 mph) ... but* LESS than the Low Gears #2 RPM Turn Off Speed 40 km/h (25 mph), gears 4 and 5 ... the* PEEC system will provide full power to accelerate the engine up to the Low Gears #2 RPM Limit (1600 rpm).

Again, if the driver really needs to obtain a higher engine rpm to be able to shift to the next higher gear, the PEEC system will allow the engine to accelerate very slowly up to the Top Engine Limit.

Top Engine Limit can be achieved when the vehicle is NOT in gear to allow downshifting.

Full engine power can be achieved after downshifting if needed on steep grades.

In this example, the PEEC system provides:

Full engine power for engine operation up to the Top Engine Limit ... when

* The vehicle speed is between the Low Gears #2 Turn Off Speed 40 km/h (25 mph) ... and* The Higher Gears Turn On Speed 77 km/h (48 mph) for gears 6 and 7.

Maximum engine rpm is then restricted to the high gears rpm limit (1700 rpm) while in gear at vehicle speeds above the high gear turn on speed.

The High Gears RPM Limit is different from the Low Gears RPM Limit:

ONLY the High Gears RPM Limit can be achieved while in gear ... and

The vehicle speed is GREATER than the High Gears Turn On Speed 77 km/h (48 mph).

The Top Engine RPM Limit can be achieved for downshifting, but no engine power is applied when:

The engine rpm is GREATER than the High Gears RPM Limit (1700 rpm) ... and

When vehicle speed is GREATER than the High Gears Turn On Speed 77 km/h (48 mph).

Check Engine Light

A cab mounted check engine light is included with the PEEC engine.

The light will indicate either low oil pressure or a PEEC system fault.

If the check engine light is ON during normal engine operation, first check to insure that the engine has the proper oil pressure.

If low engine oil pressure occurs, the PEEC system will limit the maximum engine rpm that can be obtained until the oil pressure problem is corrected.

If the PEEC engine has the proper oil pressure, and the check engine light is ON, this indicates that the PEEC system has identified a malfunction or an engine speed GREATER than 2300 rpm.

If oil pressure is normal, drive vehicle to dealer for service.

If the engine has proper oil pressure but the engine rpm drops to low idle with no response from the throttle, the Cruise Control SET/RESUME switch can be used to raise the engine rpm.

Cruise mode is operational from 0 km/h (0 mph) up to HCC limit when a throttle position sensor fault is detected.

Activate the SET position to increase rpm and vehicle speed.

When the clutch is depressed to change gears, the rpm will lower toward low idle.

After the next gear is selected, activate the RESUME position to increase engine rpm and vehicle speed.

REPEAT until the desired vehicle speed is obtained.

Acceleration rates in this mode will be significantly slower.

Do NOT use this mode to downshift due to slower engine response.

The Check Engine Light as a Diagnostic Tool

The check engine warning light can be used to communicate the specific PEEC system diagnostic fault.

This can be done by connecting a push button momentary switch from position E of connector P1 to ground on engines without a permanent fault logging personality module.

With the momentary switch depressed, the check engine light will begin to flash:

* The same fault code will be repeated once after a five second pause.

Any additional fault codes will follow and will be displayed in the same manner.

NOTE: The cycle will continue while the momentary switch is depressed.

* If no detected faults were found in the PEEC System, a code 55 will be displayed.

If any other code is displayed, contact an authorized Caterpillar dealer for assistance.

For engines equipped with permanent fault logging and cruise control:

Turn the cruise control ON/OFF switch to the OFf position, and then ...

Hold the SET/RESUME switch in the RESUME position.

When the check engine light begins to flashout (display) the diagnostic codes, the RESUME button can be released.

All current faults as well as all fault codes since the key was turned ON will be broadcast.

Faults With Throttle Response

With certain PEEC faults active, the cruise control will not function, but the engine will respond to changes in the throttle position.

The vehicle should be driven to a dealer for service ONLY if the engine oil pressure gauge indicates normal engine oil pressure.

Faults Without Throttle Response

If the check engine light is ON and the engine does not respond to changes in throttle position, the vehicle should be driven to a dealer ONLY if the oil pressure gauge indicates normal engine oil pressure.

To drive the truck, turn on the cruise ON/OFF switch, operate the vehicle using the SET/RESUME Cruise Control switch to raise and lower the engine rpm.

The Cruise Control mode is operational from 0 km/h (0 mph) up to the HCC Cruise Control limit when the PEEC control unit does not respond to changes in throttle position.

Cruise control MUST be reselected after each gear change.

Diagnostic Codes

Some trucks may have electronic dashboards that provide a direct readout of PEEC engine diagnostic codes.

Follow the truck manufacturer's instructions to obtain engine diagnostic codes.

The following is a list of 3406B PEEC diagnostic codes and their descriptions:

PEEC Component Warranty and Programming Responsibility

PEEC Components Supplied By Caterpillar

Caterpillar On-Highway Vehicle Warranty covers those PEEC components that Caterpillar supplies for the PEEC System.

Refer to PEEC System Wiring Schematic, in this instruction.

The schematic illustrates which components, including wiring and connectors, are supplied by Caterpillar and which are supplied by the OEM.

Initial Programming

Initial programming refers to PEEC programming that is required at the time of vehicle purchase to meet the customers requested parameters.

Caterpillar's responsibility is to correct defects in material or workmanship during the warranty period.

Thus, initial parameter programming of PEEC by a Caterpillar dealer, TEPS dealer or the OEM is not a warrantable expense.

Reprogramming

Reprogramming refers to any PEEC programming that is performed after vehicle delivery to the customer.

Reprogramming of PEEC that is associated with a warrantable repair is a warrantable expense.

PEEC System Wiring Diagram

PEEC System Wiring Schematic