COVER 1958254 - Caterpillar

Illustration 5 g01118589
Small terminals for the air inlet heater relay's control circuit (typical example)
Disconnect the wires from the small terminals for the air inlet heater relay's control circuit.
Restore power to the ECM.
Start the "Air Inlet Heater Override" on Cat ET. Note: The "Air Inlet Heater Override" has a one minute timer in order to disable the test when the time expires.
Stop the "Air Inlet Heater Override".
Remove power from the ECM. Expected Result:The short circuit diagnostic code 06 changed to an open circuit diagnostic code 05 when the control wires to the air inlet heater relay were disconnected.Results:
OK - The short circuit diagnostic code changed to an open circuit diagnostic code.Repair: There is a short circuit in the air inlet heater relay. Replace the air inlet heater relay and clear the diagnostic codes. Verify that the repair eliminates the problem.STOP
Not OK - The short circuit diagnostic code did not change. Proceed to Test Step 5.Test Step 5. Check the Operation of the ECM by Creating an Open and Short at the ECM Connector
Check the operation of the ECM by creating an open at the ECM.
Remove power from the ECM.
Disconnect the P2 ECM connector. Thoroughly inspect both halves of the connector for signs of corrosion and/or for moisture.
Remove the wires for the air inlet heater relay from the P2 ECM connector. Install wire jumpers with Deutsch sockets into the sockets for the air inlet heater relay. Ensure that the wire jumpers are not touching any other wires. Reconnect the P2 connector.
Restore power to the ECM.
Start the "Air Inlet Heater Override" on Cat ET. Note: The "Air Inlet Heater Override" has a one minute timer in order to disable the test when the time expires.A 05 diagnostic code should be active for the air inlet heater relay.
Remove power from the ECM.
Check the operation of the ECM by creating a short at the ECM.
Install a jumper wire between the two wire jumpers for the air inlet heater relay that were installed in the previous step.
Restore power to the ECM.
Start the "Air Inlet Heater Override" on Cat ET. Note: The "Air Inlet Heater Override" has a one minute timer in order to disable the test when the time expires.A 06 diagnostic code should be active for the air inlet heater relay.
Remove power from the ECM.
Remove the wire jumpers and reconnect ECM connector J2/P2. Expected Result:An open circuit diagnostic code 05 is active when the wires for the air inlet heater relay are removed from the ECM connector. A short circuit diagnostic code 06 is active when the jumper wire is installed across the wires for the air inlet heater relay.Results:
OK - The ECM is working properly. The problem is in the wiring between the ECM and the air inlet heater relay.Repair: Repair the wires and/or the connector.STOP
Not OK - One of the following conditions exists: The open circuit diagnostic code 05 is not active when the harness is disconnected. The short circuit diagnostic code 06 is not active when the jumper wire is installed.Repair: