C7.1 Industrial Engine and Generator Set Caterpillar

This procedure covers the following codes:

Note: A 3509-XX diagnostic code indicates a fault in the 5 VDC circuit on the J2/P2 connector. A 3510-XX diagnostic code indicates a fault in the 5 VDC circuit on the J1/P1 connector.

The following background information is related to this procedure:

The ECM supplies regulated +5 VDC to the following sensors on P2:46:

• The position sensor for the intake throttle valve

• The position sensor for the NRS Valve

• Engine oil pressure sensor

The ECM supplies regulated +5 VDC to the following sensors on P2:47:

• The NRS inlet pressure sensor

• The NRS differential pressure sensor

• Fuel rail pressure sensor

• Barometric pressure sensor

• Intake manifold pressure sensor

The ECM supplies regulated +5 VDC to the following components on P2:45:

• The position sensor for the combustion air valve

• ARD pilot fuel pressure sensor

• ARD air pressure sensor

• The DPF inlet pressure sensor

• The DPF differential pressure sensor

• The inlet temperature sensor for the DPF and the ARD flame detection temperature sensor

• The aftertreatment identification module

The ECM supplies regulated +5 VDC to the analog throttle position sensors (if equipped) on P1:2.

A diagnostic code can be caused by the following conditions:

• A short circuit in the harness

• A short circuit to a voltage that is higher than 5.16 VDC

• A faulty sensor

• A faulty ECM

• An open circuit in the harness

Illustration 1	g02157878
Typical example of the schematic for the 5 VDC supply for the analog throttle position sensors

Illustration 2	g02447500
Typical example of the schematic for the 5 VDC supply from P2:46

Illustration 3	g02447501
Typical example of the schematic for the 5 VDC supply on P2:47

Illustration 4	g02447644
Typical example of the schematic for the sensors on the 5 VDC supply for the Clean Emissions Module (CEM)

Illustration 5	g02157933
Typical example of the schematic for the inlet temperature sensor for the DPF and the ARD flame detection temperature sensor

Illustration 6	g02315513
Typical example of the fuel rail pressure sensor (1) Sensor ground (3) 5 VDC supply

Note: The position of the terminal for the voltage supply on the fuel rail pressure sensor is different to all other engine pressure sensors.

Illustration 7	g02315514
Typical example of an engine pressure sensor (1) 5 VDC supply (2) Sensor ground

Illustration 8	g02315533
Typical example of the connector for the intake throttle valve (1) 5 VDC supply (3) Sensor ground

Illustration 9	g02315534
Typical example of the connector for the NRS valve (1) 5 VDC supply (2) Sensor ground

Illustration 10	g02315535
Typical example of the connector for the combustion air valve (1) 5 VDC supply (2) Sensor ground

Illustration 11	g02315536
Typical example of the connector for the inlet temperature sensor for the DPF and the ARD flame detection temperature sensor (1) 5 VDC supply (2) Sensor ground

Illustration 12	g02315537
Typical example of the connector for the aftertreatment identification module (1) 5 VDC supply (6) Ground

Illustration 13	g02158533
Typical example of the P1 pin location for the 5 VDC supply for the analog throttle position sensors (2) 5 VDC supply (3) Ground

Illustration 14	g02027957
Typical example of the pin locations for the 5 VDC supply on the P2 connector (45) 5 VDC supply for the CEM (46) 5 VDC supply #1 (47) 5 VDC supply #2 (55) CEM ground (56) Ground #1 (57) Ground #2

Test Step 1. Check for Connector Damage

1. Turn the keyswitch to the OFF position.

2. Check the connectors and the harness for the following faults:
   • Damage

   • Abrasion

   • Corrosion

   • Incorrect attachment

3. Refer to Troubleshooting, "Electrical Connectors - Inspect".

4. Perform a 45 N (10 lb) pull test on each of the wires in the harness that are associated with the throttle position sensor. Check the wire connectors for all the sensors on the 5 VDC supply circuits.

5. Check the screws for the ECM connectors for the correct torque of 6 N·m (53 lb in).

Expected Result:

The connectors and the harness should be free of the following faults: damage, abrasion, corrosion and incorrect attachment.

Results:

• No faults found - Proceed to Test Step 2.

• Found damage, abrasion, corrosion, or incorrect attachment -

  Repair: Repair the connectors or the harness and/or replace the connectors or the harness.Use the electronic service tool in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.

  STOP

Test Step 2. Check for Active Diagnostic Codes

1. Connect the electronic service tool to the diagnostic connector.

2. Turn the keyswitch to the ON position.

3. Use the electronic service tool in order to monitor the diagnostic codes. Check and record any active diagnostic codes.

   Note: Wait at least 15 seconds in order for the diagnostic codes to become active.

Results:

• Diagnostic code 3509-4 or 3510-4 is active - Proceed to Test Step 4.

• Diagnostic code 3509-3 or 3510-3 is active - Proceed to Test Step 8.

• An XXXX-21 diagnostic code is active - Proceed to Test Step 3.

• No 5 VDC sensor supply circuit diagnostic codes are active - The fault may be intermittent. Proceed to Test Step 10.

Test Step 3. Measure the Sensor Supply Voltage

1. Turn the keyswitch to the OFF position.

2. Disconnect the sensor that relates to the active XXXX-21 code from the engine harness. Refer to Table 1.

3. Turn the keyswitch to the ON position.

4. Measure the voltage at the connector for the sensor from the terminal for the 5 VDC Supply to the sensor common terminal.

Results:

• The voltage from the terminal for the 5 VDC supply to the sensor common terminal measures 4.84 to 5.16 VDC. - The sensor supply voltage is correct.

  Repair: Perform the following repair:

  1. Temporarily connect a new sensor to the harness but do not install the new sensor in the engine.

  2. Use the electronic service tool to verify that the replacement sensor eliminates the fault.

  3. If the diagnostic code is eliminated, install the replacement sensor.

  4. Use the electronic service tool to clear the logged diagnostic codes.

  STOP

• The sensor supply voltage is out of the nominal range. - The fault is in the harness.

  Repair: Perform the following repair:

  1. Repair the faulty harness or replace the faulty harness.

  2. Use the electronic service tool in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.

  STOP

Test Step 4. Disconnect the Sensors

1. Turn the keyswitch to the ON position.

2. Use the electronic service tool in order to monitor the diagnostic codes.

3. If a 3510-4 diagnostic code is displayed, disconnect the analog throttle position sensors (if equipped) one at a time.

4. If a 3509-4 diagnostic code is displayed, disconnect the sensors on the 5 VDC supply circuits on the J2/P2 connector one at a time. Wait for 30 seconds after each sensor is disconnected.

   Note: Diagnostic code 3509-4 or 3510-4 will become inactive when the sensor that caused the 5 VDC diagnostic code is disconnected.

5. Ensure that all the sensors on the 5 VDC supply circuits are disconnected.

Expected Result:

The 5 VDC diagnostic code is not active when all of the sensors are disconnected.

Results:

• Diagnostic code 3509-4 and diagnostic code 3510-4 are not active when all of the sensors are disconnected. -

  Repair: Reconnect all of the sensors except the suspect sensor.

  Proceed to Test Step 5.

• Diagnostic code 3509-4 or 3510-4 is still active. -

  Repair: Leave all of the sensors disconnected.

  Proceed to Test Step 6.

Test Step 5. Install a New Sensor

1. Install the connector on a replacement sensor. Do not install the replacement sensor on the engine.

2. Use the electronic service tool in order to monitor the diagnostic codes.

Expected Result:

The following diagnostic codes are not active:

• 3509-3 Sensor Supply Voltage 1 : Voltage Above Normal

• 3510-3 Sensor Supply Voltage 2 : Voltage Above Normal

• 3509-4 Sensor Supply Voltage 1 : Voltage Below Normal

• 3510-4 Sensor Supply Voltage 2 : Voltage Below Normal

Results:

• No 5 VDC diagnostic codes are active. -

  Repair: Use the electronic service tool in order to clear all logged diagnostic codes. Remove the suspect sensor and then install the replacement sensor. Install the connector on the sensor.Verify that the repair eliminates the fault.

  STOP

• A 5 VDC diagnostic code is still active. -

  Repair: Do not use the new sensor.

  Proceed to Test Step 6.

Test Step 6. Remove the Pins for the 5 VDC Supply from the ECM Connector and Check for Active Diagnostic Codes

1. Turn the keyswitch to the OFF position.

2. Connect the electronic service tool to the diagnostic connector.

3. Check the ECM connectors for corrosion and moisture.

4. For a 3509-4 diagnostic code, perform the following steps:

   1. Disconnect the P2 connector from the ECM.

   2. Temporarily remove pins P2:45, P2:46 and P2:47.

   3. Reconnect connector P2 to the ECM.

5. For a 3510-4 diagnostic code, perform the following steps:

   1. Disconnect the P1 connector from the ECM.

   2. Temporarily remove pin P1:2.

   3. Reconnect connector P1 to the ECM.

6. Turn the keyswitch to the ON position.

7. Check for active diagnostic codes on the electronic service tool.

Results:

• Diagnostic code 3510-4 was previously active and is no longer active - Replace all wires on the P1 connector to the original configuration. Proceed to Test Step 9.

• Diagnostic code 3509-4 was previously active and is no longer active - Do not replace pins P2:45, P2:46 and P2:47. Proceed to Test Step 7.

• Not OK - The 5 VDC diagnostic codes are still active.

  Repair: Perform the following repair:

  1. Make sure that the latest flash file for the application is installed in the ECM. Refer to Troubleshooting, "Flash Programming".

  2. Contact the Technical Communicator at a Caterpillar dealer.

     Note: This consultation can greatly reduce the repair time.

  3. If the Technical Communicator recommends the use of a test ECM, install a test ECM. Refer to Troubleshooting, "Replacing the ECM".

  4. Use the electronic service tool to recheck the system for active diagnostic codes.

  5. If the fault is resolved with the test ECM, reconnect the suspect ECM.

  6. If the fault returns with the suspect ECM, replace the ECM.

  7. Use the electronic service tool in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.

  STOP

Test Step 7. Reconnect the pins for the 5 VDC supply one at a time and check for active diagnostic codes

1. Disconnect the P2 connector from the ECM.

2. Replace one of the following pins:
   • P2:45

   • P2:46

   • P2:47

3. Reconnect the P2 connector to the ECM.

4. Check for active diagnostic codes on the electronic service tool.

Results:

• A 3509-XX diagnostic code is active. - Make a note of the pin that was replaced and proceed to Test Step 9.

• No 3509-XX diagnostic codes are active. - Remove the pin that was previously replaced and then repeat Test Step 7 for the other two pins one pin at a time.

Test Step 8. Check the 5 VDC Supply from the ECM

1. For a 3510-3 diagnostic code, perform the following steps:

   1. Disconnect the P1 connector from the ECM.

   2. Check the ECM connector for corrosion and moisture. Refer to Troubleshooting, "Electrical Connectors - Inspect".

   3. Remove the wire from P1:2.

   4. Install a jumper wire to P1:2.

   5. Measure the voltage from the end of the jumper wire to P1:3.

2. For a 3509-3 diagnostic code, perform the following steps:

   1. Disconnect the P2 connector from the ECM.

   2. Check the ECM connector for corrosion and moisture. Refer to Troubleshooting, "Electrical Connectors - Inspect".

   3. Remove the wires from P2:46 and P2:47.

   4. Install a jumper wire to P2:46.

   5. Measure the voltage from the end of the jumper wire to P2:56.

   6. Install a jumper wire to P2:47.

   7. Measure the voltage from the end of the jumper wire to P2:57.

Expected Result:

The measured voltages should be 5.0 ± 0.16 VDC.

Results:

• The voltage is within the expected range. - Proceed to Test Step 9.

• The voltage is not within the expected range. -

  Repair: Perform the following repair:

  1. Make sure that the latest flash file for the application is installed in the ECM. Refer to Troubleshooting, "Flash Programming".

  2. Contact the Technical Communicator at the Caterpillar Dealer.

     Note: This consultation can greatly reduce the repair time.

  3. If the Technical Communicator recommends the use of a test ECM, install a test ECM. Refer to Troubleshooting, "Replacing the ECM".

  4. Use the electronic service tool to recheck the system for active diagnostic codes.

  5. If the fault is resolved with the test ECM, reconnect the suspect ECM.

  6. If the fault returns with the suspect ECM, replace the ECM.

  7. Use the electronic service tool in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.

  STOP

Test Step 9. Measure the +5 VDC Supply to the Sensor

1. Turn the keyswitch to the ON position.

2. For a 3510-XX diagnostic code, perform the following steps:

   1. Disconnect the analog throttle position sensors.

   2. Measure the voltage between terminal A (analog throttle position sensors +5 Volts) and the engine ground for each of the analog throttle position sensors.

3. For a 3509-XX diagnostic code, perform the following steps:

   1. Disconnect all of the sensors that are supplied with 5 VDC from the pin that was previously identified.

   2. Measure the voltage between the terminal for the 5 VDC supply and the engine ground on the connector for each of the sensors.

Expected Result:

The voltage is 5.0 ± 0.16 VDC.

Results:

• OK - The +5 VDC supply is within the expected range. Proceed to Test Step 10.

• Not OK - The voltage is greater than 5.16 VDC.

  Repair: Check the +5 VDC supply wire for a short to a higher voltage source.Repair the +5 VDC supply wire and/or replace the +5 VDC supply wire.Use the electronic service tool in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.

  STOP

• Not OK - The voltage is less than 4.84 VDC.

  Repair: Check the +5 VDC supply wire for a short to ground.Repair the +5 VDC supply wire and/or replace the +5 VDC supply wire.Use the electronic service tool in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.

  STOP

Test Step 10. Perform the "Wiggle Test" on the Electronic Service Tool

1. Select the "Wiggle Test" from the diagnostic tests on the electronic service tool.

2. Choose the appropriate group of parameters to monitor.

3. Press the "Start" button. Wiggle the wiring harness in order to reproduce intermittent faults.

If an intermittent fault exists, the status will be highlighted and an audible beep will be heard.

Expected Result:

No intermittent faults were indicated during the "Wiggle Test".

Results:

• OK - No intermittent faults were found. The harness and connectors appear to be OK. If you were sent from another procedure, return to the procedure and continue testing. If this test has resolved the fault, return the engine to service.STOP

• Not OK - At least one intermittent fault was indicated.

  Repair: Repair the harness or the connector.Use the electronic service tool in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.

  STOP