Normal Operation: Notes

The PCM monitors the generator output via the GENMON circuit. The PCM uses the GENCOM circuit to command the generator to either increase or decrease output. If the GENCOM circuit (generator control circuit) or the A sense circuit is open or shorted to ground, the PCM will be unable to control the generators output. When the engine rises above approximately 2, 000 rpm, the generator defaults to a steady voltage of approximately 13.5 volts and the PCM sends a request to the Instrument Cluster (IC) to illuminate the charging system warning indicator.

• DTC P0620 Generator Control Circuit - If the GENCOM circuit or A sense circuit are open or shorted to ground the PCM sets this DTC.

This pinpoint test is intended to diagnose the following: 

• Fuse
• Wiring, terminals or connectors
• Generator
• PCM