Pcm Controlled Generator: 5.7L
- Install scan tool. Start engine. Using scan tool, monitor generator terminal "L" terminal. If scan tool displays generator terminal "L" active, perform DTC P1637 test. See appropriate SELF-DIAGNOSTICS article. If scan tool does not display generator terminal "L" active, go to next step.
- Using DVOM, measure voltage at battery. If voltage is 13-15 volts, check for low battery charge. A shorted output diode, malfunctioning regulator, an open or shorted rotor, or an open sense lead in generator may cause a low battery charge. If voltage is not 13-15 volts, go to next step.
- Using test light connected to ground, probe generator battery feed circuit. If test light illuminates, go to next step. If test light does not illuminate, check charging system.
- Disconnect generator harness connector. Start engine. Using DVOM, measure voltage between ground and generator harness connector terminal "B" (Brown wire). If voltage is 10 volts or more, go to step 9. If voltage is less than 10 volts, go to next step.
- Turn ignition off. Disconnect PCM harness connector C2. Using DVOM, check for continuity between generator harness connector terminal "B" (Brown wire) and PCM harness connector C2 terminal No. 15 (Brown wire). If continuity exists, go to step 7. If continuity does not exist, go to next step.
- Repair open or high resistance in generator circuit (Brown wire).
- Check for poor connection at PCM. Repair as necessary. If connection is okay, go to next step.
- Replace PCM.
- Check for poor connection at generator. Repair as necessary. If connection is okay, go to next step.
- Replace generator.