Normal Operation: Notes

WARNING: This page is about a different car, the 2012 Ford Pickup, 2012 Ford F550 Super Duty, 2012 Ford F450 Super Duty, and 2012 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

The PCM monitors the generator output via the generator monitor (GENMON) circuit. The PCM uses the generator command (GENCOM) circuit to command the generator to either increase or decrease output. If the GENCOM circuit (generator control circuit) or the "A" sense circuit are open or shorted to ground, the PCM will not be able to control the generator output. When the engine speed is greater than approximately 2, 000 rpm, the generator defaults to a steady voltage output of approximately 13.5 volts and the PCM sends a message over the High Speed Controller Area Network (HS-CAN) to the Instrument Panel Cluster (IPC) through the Body Control Module (BCM) to illuminate the charging system warning indicator lamp.

DTC P0620 (Generator Control Circuit) - The PCM sets this DTC if the GENCOM circuit or "A" sense circuit is open or shorted to voltage or ground.

This pinpoint test is intended to diagnose the following:

Fusible link
Wiring, terminals or connectors
Generator
PCM