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

WARNING: This page is about a different car, the 2003 Ford Pickup, 2003 Ford F550 Super Duty, 2003 Ford F450 Super Duty, and 2003 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

Check 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. If no DTCs exist, go to next step. If any DTCs exist, perform appropriate test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS under SELF-DIAGNOSTIC SYSTEM.

Check The System For Overcharging

Turn ignition switch to LOCK position. Disconnect NGS tester. Start engine and let idle. Turn off all accessories. Measure voltage between primary battery terminals while varying engine speed. If voltage is less than 15.5 volts, go to next step. If voltage is 15.5 volts or more, go to TEST G: SYSTEM OVERCHARGES (BATTERY VOLTAGE GREATER THAN 15 VOLTS) .

Check The Charging System Warning Indicator Operation

Turn ignition switch to LOCK position. Connect lower generator connector. Disconnect PCM connector C175 or connector C1381c. PCM is located at left rear of engine compartment. Turn ignition switch to RUN position. Observe warning indicator. If warning indicator illuminates, go to next step. If warning indicator illuminates, go to step 5.

Check The Warning Indicator Circuit

Turn ignition switch to LOCK position. Disconnect instrument cluster connector C220b. Instrument cluster connector C220b is located behind instrument cluster. Measure resistance between ground and 7.3L PCM connector C175 terminal No. 67 (Light Green/Red wire) or 6.0L PCM connector C1381c terminal No. 30 (Violet wire). See Figure or Figure . If resistance is more than 10 k/ohms, see appropriate ANALOG INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT for further diagnosis. If resistance is not more than 10 k/ohms, repair circuit. See WIRING DIAGRAMS . Test system for normal operation.

Check The Lower Generator "A" Circuit

Turn ignition switch to LOCK position. Connect upper generator connector. Disconnect lower generator 3-pin connector. Turn ignition switch to RUN position. Measure voltage between ground and lower generator harness connector terminal No. 3 (Orange/Light Blue wire). See Figure or Figure . If battery voltage is present, go to next step. If battery voltage is not present, repair circuit between lower generator and Fusible Link "H". See WIRING DIAGRAMS .

Check For Correct PCM Operation

Disconnect PCM harness connector. Inspect PCM harness connector for corrosion and pushed out pins. Connect PCM harness connector, ensuring it is connected properly. Connect all disconnected connectors. Operate system. If fault is still present, replace PCM. If fault is not present, system is operating properly at this time.