GM Service Manual Online
For 1990-2009 cars only

PCM Controlled Generator

The generator provides voltage to operate the vehicle's electrical system and to charge its battery. A magnetic field is created when current flows through the rotor. This field rotates as the rotor is driven by the engine, creating an AC voltage in the stator windings. The AC voltage is converted to DC by the rectifier bridge and is supplied to the electrical system at the battery terminal.

When the ignition switch is on, voltage is supplied to terminal L by the Powertrain Control Module (PCM), turning on the regulator. The generator's voltage regulator controls current to the rotor, thereby controlling the output voltage. The rotor current is proportional to the electrical pulse width supplied by the regulator. When the engine is started, the regulator senses generator rotation by detecting AC voltage at the stator through an internal wire.

The PCM commands the charge indicator on by ground the charge indicator control circuit when the PCM detects a charging system problem.

The generator features permanently lubricated bearings. The generator is replaced as a complete unit, service should only include the tightening of mounting components.

Generator Usage

Application

Specification

Model

CS130D

Rated Output

100A

Load Test

70A

RPO

K60