Generator Control System Test
NOTE:
Generator may also be referred to as alternator.
- Disconnect generator 4-pin connector. Start engine. Turn on headlights (high beam). Measure voltage between generator 4-pin connector terminal No. 1 (White/Green wire) and battery positive terminal. See Figure. If one volt or less exists, go to step 3). If greater than one volt exists, go to next step.
- Turn headlights and ignition off. Disconnect 32-pin connector from Electronic Control Module/Powertrain Control Module (ECM/PCM), located behind right kick panel. Check continuity of Alternator Control (ALTC) circuit (White/Green wire) between ECM/PCM connector terminal No. 19 and ground. See Fig 1. If continuity exists, repair short to ground in White/Green wire. If continuity does not exist, install known good ECM/PCM and recheck system. Replace ECM/PCM if necessary.
- Turn headlights and ignition off. Disconnect 32-pin connector from ECM/PCM, located behind right kick panel. Check continuity of ALTC circuit (White/Green wire) between ECM/PCM connector terminal No. 19 and 4-pin generator connector terminal No. 1. See Figure and Fig 1 . If continuity does not exist, repair open in White/Green wire. If continuity exists, test alternator and regulator. See GENERATOR/REGULATOR OUTPUT TEST .