Alternator Control

The IPC initiates the generator operation by supplying 12 V, through an internal resistor at IPC connector C1 terminal A9 to the generator L terminal, through CKT 225 (RED). The IPC enables the generator operation with the ignition in the following positions:
^ RUN
^ START
The generator regulator in turn applies voltage to the rotor as a pulse width modulated signal in order to energize the field windings.

The IPC also monitors the voltage of the generator at the IPC connector C1 terminal A9, CKT 225 (RED), in order to determine if the generator is functioning properly. The regulator grounds the L terminal when a internal problem is detected. When the engine is not running, the generator grounds CKT 225 (RED). The regulator can detect any of the following faults:
^ A shorted output diode
^ A malfunctioning regulator
^ An open or shorted rotor
^ An under or over voltage condition
^ A shaft not rotating

The IPC senses this ground. If the engine is running, BATTERY NOT CHARGING is displayed on the driver information center. For export vehicles, the BATTERY indicator also illuminates on the IPC.