3408E and 3412E Engines for Caterpillar Built Machines Caterpillar

The Electronic Control Module (ECM) detects an injection actuation pressure that is greater than 24000 kPa (3480 psi) for at least one second.

System Response:

The ECM will log the event. The status of "Injector Actuation Current" parameter on Caterpillar Electronic Technician (ET) will ramp to zero percent.

• Low power

Test Step 1. Use Cat ET to Perform the "Injection Actuation Pressure Override Test"

1. Start the engine and run the engine at low idle speed.

2. Start the "Injection Actuation Pressure Test" on Cat ET.

3. Increase "Desired Injection Actuation Pressure" to 21500 kPa (3100 psi). Record the "Injection Actuation Pressure".

4. Decrease "Desired Injection Actuation Pressure" to 8000 kPa (1150 psi). Record the "Injection Actuation Pressure".

Expected Result:

The "Desired Injection Actuation Pressure" and the "Injection Actuation Pressure" remain within 2000 kPa (290 psi) of each other.

Results:

• OK - The system is working properly. There may be an intermittent problem.

  Repair: Refer to Troubleshooting, "Electrical Connectors - Inspect".

  STOP

• Not OK - Proceed to Test Step 2.

Test Step 2. Disconnect the Injection Actuation Pressure Sensor

1. Turn the keyswitch to the ON position.

2. Disconnect the injection actuation pressure sensor.

3. Monitor the Cat ET status screen and verify that "Injection Actuation Pressure" defaults to approximately 12000 kPa (1750 psi).

4. Reconnect the injection actuation pressure sensor.

Expected Result:

The "Injection Actuation Pressure" defaults to approximately 12000 kPa (1750 psi) when the sensor is disconnected.

Results:

• OK - The pressure defaults to the proper value. Proceed to Test Step 3.

• Not OK - The pressure reading is not approximately 12000 kPa (1750 psi). The problem is in the circuit for the injection actuation pressure sensor.

  Repair: Troubleshoot the circuit for the injection actuation pressure sensor. Refer to Troubleshooting, "Engine Sensor Open/Short Circuit - Test" for the proper procedure.

  STOP

Test Step 3. Temporarily Install a New Injection Actuation Pressure Sensor

1. Turn the keyswitch to the OFF position.

2. Temporarily install a new injection actuation pressure sensor.

3. Start the engine and run the engine at low idle speed.

4. Start the "Injection Actuation Pressure Test" on Cat ET.

5. Increase "Desired Injection Actuation Pressure" to 12000 kPa (1750 psi). Record the "Injection Actuation Pressure".

6. Decrease "Desired Injection Actuation Pressure" to 8000 kPa (1150 psi). Record the "Injection Actuation Pressure".

Expected Result:

The "Desired Injection Actuation Pressure" and the "Injection Actuation Pressure" remain within 2000 kPa (290 psi) of each other.

Results:

• OK - The system is working properly.

  Repair: Permanently install the new sensor. Verify that the repair eliminates the problem.

  STOP

• Not OK - The problem appears to be with the injection actuation pressure control system.

  Repair: Troubleshoot the circuit for the injection actuation pressure control valve. Refer to Troubleshooting, "Injection Actuation Pressure Control Valve Circuit - Test" for the proper procedure.

  STOP