GM Service Manual Online
For 1990-2009 cars only

The starter solenoid windings are energized when the ignition switch is turned to START and the clutch pedal position (CPP) switch (manual transaxle) or the park/neutral position (PNP) switch (automatic transaxle) is closed. The CPP switch (manual transaxle) provides voltage to the starter windings when the clutch pedal is depressed. The park/neutral position switch (automatic transaxle) provides voltage to the starter windings when the manual selector lever is in the P or N position. The resulting plunger and pinion drive lever movement causes the drive pinion to engage the engine flywheel ring gear. This movement also causes the starter solenoid contacts to close. With the contacts closed, the starter solenoid provides a closed circuit between the battery positive (+) terminal and the starter assembly. Because the starter assembly is permanently grounded to the engine block, the circuit is complete and cranking occurs as soon as the starter solenoid contacts close. When the engine starts, the drive assembly is designed to overrun and protect the armature from excessive speed until the ignition switch released from the START position. With the ignition switch released, voltage is removed from the starter solenoid and the windings de-energize. When the starter solenoid de-energizes, the return spring in the starter solenoid forces the contacts open, breaking the circuit between the battery and the starter solenoid, and disengages the drive assembly.