5036315 JOHNSON MOUNT, UPPER Port

Illustration 1 g01642422
Schematic for the compression brakesTest Step 1. Inspect Electrical Connectors and Wiring
Turn the keyswitch to the OFF position.
Thoroughly inspect the valve cover connectors and the firewall bulkhead connector. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.Expected Result:All connectors, pins, and sockets are coupled and/or inserted and the harness and wiring are free of corrosion, of abrasion and of pinch points.Results:
OK - The harness and wiring are OK. Proceed to Test Step 2.
Not OK - There is a problem in the connectors and/or wiring.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are coupled.Verify that the repair eliminates the problem.STOPTest Step 2. Check for Active Diagnostic Codes and/or Logged Diagnostic Codes
Establish communication between Cat ET and the engine ECM.
Access the "Special Tests" under the "Diagnostics" menu.
Start the "Retarder Brake Test" on Cat ET.
Once Cat ET displays the status of the engine retarder solenoid, stop the "Retarder Brake Test".
Check for active diagnostic codes and/or logged diagnostic codes that are associated with the compression brake.Expected Result:No diagnostic codes are active.Results:
OK - No diagnostic codes are active. If a problem is suspected with the "Engine Retarder Solenoid Selector Switch", proceed to Test Step 9.
Not OK - A low current diagnostic code (-5) is active. Proceed to Test Step 3.
Not OK - A high current diagnostic code (-6) is logged. Proceed to Test Step 5.Test Step 3. Short the Wires of the Suspect Engine Retarder Solenoid at the Valve Cover Connector
Turn the keyswitch to the OFF position.
Disconnect the valve cover connector for the suspect engine retarder solenoid.
Use a jumper wire in order to create a short circuit between the supply and the return for the engine retarder solenoid. If you are troubleshooting a 1072 code, install the jumper wire between terminals 2 and 3. If you are troubleshooting a 1073 code, install the jumper wire between terminals 1 and 3.
Turn the keyswitch to the ON position.
Access the "Special Tests" under the "Diagnostics" menu.Note: The "Retarder Brake Test" will not work if the switch in the cab for the retarder is OFF.
Start the "Retarder Brake Test" on Cat ET.
Once Cat ET displays the status of the engine retarder solenoid, stop the "Retarder Brake Test".
Check for active diagnostic codes and/or logged diagnostic codes that are associated with the compression brakes.Expected Result:A high current diagnostic code (-6) is logged.Results:
OK - A high current diagnostic code (-6) is logged. The harness wiring between the valve cover connector for the suspect engine retarder solenoid and ECM connector P2 is OK. Proceed to Test Step 7.
Not OK - A low current diagnostic code -5 is active at this time. The ECM did not detect the short at the valve cover connector for the engine retarder solenoid. Proceed to Test Step 4.Test Step 4. Create a Short Circuit at the ECM
Turn the keyswitch to the OFF position.
Disconnect the P2 connector.
Inspect the terminals on the J2 and P2 ECM connectors for damage.
Remove the return wire and the supply wire for the suspect engine retarder solenoid from the P2 connector.
Use a jumper wire in order to short the two pins for the suspect engine retarder solenoid at the P2 connector.
Connect the J2/P2 connectors.
Turn the keyswitch to the ON position.Note: The "Retarder Brake Test" will not work if the switch in the cab for the retarder is OFF.
Access the "Special Tests" under the "Diagnostics" menu. Start the "Retarder Brake Test" on Cat ET.
Once Cat ET displays the status of the engine retarder solenoid, stop the "Retarder Brake Test".
Check for active diagnostic codes and/or logged diagnostic codes that are associated with the retarder solenoids.Expected Result:A high current diagnostic code (-6) is logged.Note: Disconnecting a single supply wire for the engine retarder solenoids causes an open circuit for the solenoids that share the supply wire.Results:
Yes - A high current diagnostic code (-6) is logged. The ECM detected the short circuit.Repair: Check the continuity of the supply wire for the suspect engine retarder solenoid between the valve cover connector for the suspect engine retarder solenoid and the P2 connector. Make any necessary repairs.Check the continuity of the return wire for the suspect engine retarder solenoid between the valve cover connector for the suspect engine retarder solenoid and P2. Make any necessary repairs.STOP
No - A low current diagnostic code -5 is active. The ECM did not detect the short circuit.Repair: Replace the ECM. Refer to Troubleshooting, "Replacing the ECM".Verify that the repair eliminates the problem.STOPTest Step 5. Open the Wires for the Suspect Eng