SEAL-PISTON 3406340 - Caterpillar

code screen on Cat ET. Check and record any active diagnostic codes.Note: Wait at least 30 seconds in order for the diagnostic codes to become active.Expected Result:No diagnostic codes are active.Results:
OK - No diagnostic codes are active, but a problem is suspected in the prelube system. Proceed to Test Step 6.
Not OK - A 06 diagnostic code is active at this time. Proceed to Test Step 3.
Not OK - A 05 diagnostic code is active at this time. Proceed to Test Step 4.Test Step 3. Create an Open at the Connector for the Prelube Relay
Turn the keyswitch to the OFF position.
Disconnect the connector for the prelube relay.
Turn the keyswitch to the ON position.
Proceed to the "Diagnostic Overrides" screen on Cat ET.
Activate the prelube system.Note: Monitor the "Active Diagnostic Codes" screen on Cat ET.
Check for a 05 diagnostic code for the prelube relay.Note: Wait at least 30 seconds in order for the diagnostic codes to become active.
Turn the keyswitch to the OFF position.Expected Result:A 05 diagnostic code is now active for the prelube relay.Results:
OK - A 06 diagnostic code was active before disconnecting the connector. A 05 diagnostic code became active after disconnecting the connector. The harness and the ECM are OK. The problem may be in the prelube relay.Repair: Temporarily connect a new prelube relay to the harness, but do not install the new prelube relay. Verify that there are no active diagnostic codes for the prelube relay. If there are no active diagnostic codes for the prelube relay, permanently install the new prelube relay. Clear any logged diagnostic codes.STOP
Not OK - A 06 diagnostic code remains active. There is a short between the connector for the prelube relay and the ECM. Leave the connector for the prelube relay disconnected. Proceed to Test Step 5.Test Step 4. Create a Short at the Connector for the Prelube Relay
Turn the keyswitch to the OFF position.
Install a jumper wire between terminal 85 and terminal 86 of the connector for the prelube relay.
Turn the keyswitch to the ON position.Note: Monitor the "Active Diagnostic Codes" screen on Cat ET after installing the jumper wire.
Proceed to the "Diagnostic Overrides" screen on Cat ET.
Activate the prelube system.Note: Monitor the "Active Diagnostic Codes" screen on Cat ET.
Wait at least 30 seconds for activation of the 06 diagnostic code.
Turn the keyswitch to the OFF position. Remove the wire jumper.Expected Result:A 06 diagnostic code is active when the jumper wire is installed. A 05 diagnostic code is active when the jumper wire is removed.Results:
OK - A 06 diagnostic code is active when the jumper wire is installed. A 05 diagnostic code is active when the jumper wire is removed. The engine harness and the ECM are OK.Repair: Temporarily connect a new prelube relay to the harness, but do not install the new prelube relay. Verify that there are no active diagnostic codes for the prelube relay. If there are no active diagnostic codes for the prelube relay, permanently install the new prelube relay. Clear any logged diagnostic codes.STOP
Not