0327046 JOHNSON SCREW, Anode

Illustration 1 g01385903
Schematic for the engine's lamp circuitsNote: There is a configuration parameter that is associated with the maintenance indicator lamp. Ensure that the parameter is configured correctly prior to troubleshooting the lamp circuit. Refer to Troubleshooting, "Configuration Parameters" for information that is related to the configuration of the lamp circuits.Test Step 1. Inspect the Electrical Connectors and the Wiring
Remove electrical power from the ECM.
Illustration 2 g01377328
Locations of the connectors that are associated with the lamp circuits (rear engine view) (1) J1/P1 ECM connectors (2) Customer connectors
Thoroughly inspect connectors (1) and (2). Also, thoroughly inspect any of the other connectors that are associated with the lamp circuits. Refer to the Schematic of the engine for connector locations. Refer to Troubleshooting, "Electrical Connectors - Inspect".
Illustration 3 g01385913
Terminal locations at the P1 ECM connector that are for the lamp circuits (P1-19) Diagnostic lamp (P1-20) Warning lamp (P1-21) Maintenance indicator lamp
Illustration 4 g01385942
Terminal locations at the customer connector that are for the lamp circuits (Terminal 22) Maintenance indicator lamp (Terminal 23) Diagnostic lamp (Terminal 25) Warning lamp
Perform a 45 N (10 lb) pull test on each of the wires for the lamp circuits.
Check the torque of the allen head screw on the ECM connectors and the customer connectors. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.
Check the harness and the wiring for abrasion and for pinch points from the dash display back to the ECM.Expected Result:All of the connectors, pins and sockets are completely coupled and/or inserted and the harness and wiring are free of corrosion, of abrasion and of pinch points.Results:
OK - The harness and connectors appear to be in good repair. Proceed to Test Step 2.
Not OK - The connectors and/or wiring need repair.Repair: Repair the wiring and/or the connectors. Replace parts, if necessary. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled. Verify that the repair eliminates the problem.STOPTest Step 2. Check for Proper Operation of the Lamp Circuits
Connect Cat ET to the service tool connector.
Restore electrical power to the ECM. Turn the keyswitch to the ON position.
Select the "Override Parameters" option from the "Diagnostic Tests"on Cat ET.
Use the correct override parameter to power the circuit for the suspect lamp.
Remove electrical power from the ECM. Turn the keyswitch to the OFF position.Expected Result:The suspect lamp illuminates when the override is turned on.Results:
OK - The suspect lamp illuminates when the override is on.Repair: There does not appear to be a problem with the lamp circuit at this time. The problem may have been related to a faulty connection in the harness. Carefully reinspect the connectors and wiring. Refer to Troubleshooting, "Electrical Connectors - Inspect".STOP
Not OK - The suspect lamp does not illuminate when the override is on. Inspect the lamp and the lamp socket for the suspect circuit. Use a lamp socket that is known to be operational to check the condition of the lamp, if necessary. If either of the components are questionable, replace the component. Retest the circuit. If the problem persists or if the components of the lamp assembly appear to be in good repair, proceed to Test Step 3.Test Step 3. Use the Override to Check the Wiring Harness
Remove the lamp for the suspect circuit from the lamp socket.
Connect a test lamp between the terminal of the lamp socket that is for the driver circuit from the ECM and the correct return for the circuit:
Connect a test lamp in the following manner if the lamp uses a high side driver as an output at the ECM:Connect the test lamp between the terminal of the lamp socket that is for the driver circuit from the ECM and the −Battery terminal.
Connect a test lamp in the following manner if the lamp uses a low side driver as an output at the ECM:Connect the test lamp between the terminal of the lamp socket that is for the driver circuit from the ECM and the "R" terminal