160 RENR5042-02 Troubleshooting Section Repair: Leave the injector wires disconnected. Measure the resistance of the return wire between the P2 connector and engine ground. Proceed to Test Step 11. Not OK One or more of the injectors that were disconnected indicate “Short”. If the resistance is less than 10 Ohms, the problem is in the return wire between the ECM and the valve cover base. Repair: The problem is most likely in the common wire to the injector. Inspect the connectors for moisture and for corrosion. Also, check the common wire for exposed wires. If the resistance is greater than 10 Ohms, the problem is in the return wire under the valve cover.
Repair the injector harness or replace the injector harness. Repair the injector harness or replace the injector harness under the valve cover. Perform the “Injector Solenoid Test”. Verify that the repair eliminates the problem. Verify that the repair eliminates the problem. STOP. STOP. Test Step 11. Check for a Short Circuit in the Return Wire i02290030 Maintenance Due Lamp Circuit - Test Electrical shock hazard. The electronic unit injec- tor system uses 90-120 volts. SMCS Code: 7431-038 A. Turn the key switch to the OFF position. A strong electrical shock hazard is present if the key switch is not turned off. System Operation Description:
Use this procedure in order to troubleshoot any suspect problems with the circuit for the maintenance due lamp. B. Disconnect the P2 connector. The maintenance due lamp is a maintenance indicator that is based on the PM levels that are programmed into the Electronic Control Module (ECM). The lamp will turn ON when the programmed interval is met. C. Measure the resistance between the terminal for the common line for the problem injector in the P2 connector and engine ground. Expected Result: The resistance is greater than 10 Ohms. Results: OK – The resistance is greater than 10 Ohms. Repair: Reconnect the J2/P2 connectors. Replace the faulty injector. Perform the “Injector Solenoid Test”.
Verify that the repair eliminates the problem. STOP. Not OK – There is a short in the return line. Repair: Disconnect the connector from the valve cover base.