GM Service Manual Online
For 1990-2009 cars only

Object Number: 1209083  Size: A2

The ignition switch has four different positions.

LOCK/OFF: This position locks the ignition. The key can only be removed in LOCK/OFF.

ACC (ACC/ACCESSORY): This is the position in which you can operate the electrical accessories. Use this position if the vehicle must be pushed or towed.

ON/RUN: This position can be used to operate the electrical accessories and to display some instrument panel cluster warning and indicator lights. The switch stays in this position when the engine is running. If you leave the key in the ACC/ACCESSORY or ON/RUN position with the engine off, the battery could be drained. You may not be able to start the vehicle if the battery is allowed to drain for an extended period of time.

START: This is the position that starts the engine. When the engine starts, release the key. The ignition switch returns to ON/RUN for driving. A warning tone will sound when you park the vehicle, the driver door is opened and the key is in the ignition.