Circuit Description

Generator communicates with PCM on 2 circuits, the "L" (Light) or "F" (Field) circuit. PCM uses "L" circuit to monitor faults in charging system. The generator "L" terminal indicates whether the PCM is allowing generator to operate. PCM can disable generator under certain conditions to ease starting. Active indicates that PCM is allowing generator operation, while inactive indicates that PCM is not allowing generator operation. If the internal regulator in the generator detects a charging system fault, the regulator will ground generator "F" circuit. PCM then sends a class 2 message to turn on CHARGE indicator light.

DTC will set when either of the following conditions have been met:

• "F" terminal duty cycle is less than 5 percent for 30 seconds when engine is running and engine speed is less than 3000 RPM.
• "F" terminal duty cycle is greater than 65 percent for 5 seconds and engine is not running.