Test D: Warning Indicator On With Engine Running, System Is Charging

Check For Fault Codes In PCM

Connect New Generation Star (NGS) tester to Data Link Connector (DLC). Turn ignition switch to RUN position. Using NGS tester, perform Powertrain Control Module (PCM) self-test. Do any DTCs exist? If yes, perform appropriate test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in appropriate SELF-DIAGNOSTICS in ENGINE PERFORMANCE. If no, go to next step.

Check System For Overcharging

Start engine. With the engine running and all accessories off, measure the voltage at the battery terminals while varying the engine RPM. Is the voltage greater than 15.5 volts? If yes, go to TEST C: SYSTEM OVERCHARGES . If no, go to next step.

Check Charging System Warning Indicator Operation

With the engine running, monitor the generator output fault PID in the PCM. Does the PID read YES? If yes, go to next step. If no, see appropriate ANALOG INSTRUMENT PANEL article in ACCESSORIES & EQUIPMENT.

Check Generator Output

Verify the generator output. Perform GENERATOR LOAD TEST and GENERATOR NO-LOAD TEST under ON-VEHICLE TESTING. Did the generator pass the component tests? If yes, go to next step. If no, install a new generator. See GENERATOR under REMOVAL & INSTALLATION. Clear the DTCs. Test the system for normal operation.

Check For Correct PCM Operation

Disconnect all PCM connectors. Check for corrosion and pushed-out pins. Connect any disconnected connectors. Make sure all other system connectors are fully seated. Operate the system and verify the concern is still present. If the concern still present, install a new PCM. See appropriate REMOVAL & INSTALLATION article in ENGINE PERFORMANCE. Repeat the PCM self-test. Test the system for normal operation. If concern is not still present, the system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. Clear the DTCs. Repeat the self-test.