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

  1. Connect New Generation Star (NGS) tester to Data Link Connector (DLC). Turn ignition on. Using NGS tester, perform Powertrain Control Module (PCM) self-test. If no DTCs are retrieved, go to next step. If any Diagnostic Trouble Codes (DTC) are retrieved, perform appropriate test in accordance with DTC retrieved. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
  2. Turn ignition off. Disconnect NGS tester. Start engine. With engine running and all accessories turned off, measure voltage between battery terminals while varying engine speed. If voltage is less than 15 volts, go to next step. If voltage is greater than 15 volts, perform TEST C: SYSTEM OVERCHARGES .
  3. Turn ignition off. Disconnect generator 3-pin harness connector. Turn ignition on. Measure voltage between ground and generator harness connector terminal No. 3 (Red wire). See Figure. If battery voltage is present, go to next step. If battery voltage is not present, repair open or short in Red wire. See WIRING DIAGRAMS .
  4. Turn ignition off. Disconnect PCM harness connector C175c. Turn ignition on and observe warning indicator. If warning indicator is not illuminated, go to next step. If warning indicator is illuminated, repair short to ground in Gray/Red wire between generator and PCM. See WIRING DIAGRAMS .
  5. Turn ignition off. Reconnect PCM harness connector C175c. Reconnect generator 3-pin harness connector. Check generator output. See GENERATOR LOAD TEST  under ON-VEHICLE TESTING. If generator tests okay, go to next step. If generator does not test okay, replace generator. See GENERATOR  under REMOVAL & INSTALLATION.
  6. Disconnect PCM harness connector C175c. Inspect harness connector for pushed out pins, corrosion or bent terminals. Repair as necessary. If harness connector is okay, reconnect and retest system operation. If fault is still present, replace PCM. Clear DTCs and repeat PCM self-test. If fault is still not present, system is operating correctly at this time.
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