178 RENR5042-02 Troubleshooting Section Repair: Repair the connector and/or the wiring. 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 problem is resolved. Results: OK The warning lamp turned on while the jumper wire was connected. The warning lamp turned off when the jumper wire was removed. The +Battery side of the circuit for the warning lamp is functioning properly. There is a problem with the return wire between the warning lamp and the P1 connector. STOP. Test Step 3. Test the Warning Lamp Circuit at the ECM Connector Repair:
Repair wire F420-GN between the warning lamp and terminal P1-29. Verify that the problem is resolved. A. Disconnect the J1/P1 connectors. B. Connect a jumper wire between terminal P1-30 and engine ground. STOP. C. Turn the keyswitch to the ON position. Observe the warning lamp. Not OK – The warning lamp did not turn on when the jumper wire was connected. There is a problem with the +Battery side of the circuit for the warning lamp. Proceed to Test Step 5. D. Remove the jumper wire and observe the warning lamp. Test Step 5. Check the Voltage from the Keyswitch to the Warning Lamp Expected Result: The warning lamp turned on while the jumper was connected.
The warning lamp turned off when the jumper was removed. A. Turn the keyswitch to the OFF position. B. Remove the wire from the terminal R of the keyswitch. Results: OK – The warning lamp turned on while the jumper was connected. The warning lamp turned off when the jumper was removed. The warning lamp circuit is functioning properly. Proceed to Test Step 6. C. Turn the keyswitch to the ON position. D. Measure the voltage on terminal B of the keyswitch to engine ground. Not OK – The warning lamp did not turn on. There is a problem with the circuit for the warning lamp. Proceed to Test Step 4. E. Measure the voltage on terminal R of the keyswitch to engine ground. F.
Turn the keyswitch to the OFF position. Test Step 4. Test the Circuit at the Warning Lamp Expected Result: A. Disconnect wire F420-GN from the warning lamp. Voltage is present on terminal B and terminal R at the keyswitch. B. Connect a jumper wire between the lamp’s open terminal and engine ground. Results: OK – Voltage is present on terminal B and terminal R at the keyswitch. C. Turn the keyswitch to the ON position. Observe the warning lamp. Repair: If voltage is present on terminal R, repair the wire between the keyswitch and the warning lamp. Verify that the breaker is not tripped. Return all wiring to the original configuration. Verify that the problem is resolved. D.
Disconnect the jumper wire and observe the warning lamp. Expected Result: The warning lamp turns on while the jumper is connected. The warning lamp turns off when the jumper is disconnected. STOP. Not OK – Voltage is not present on terminal B at the keyswitch.