GM Service Manual Online
For 1990-2009 cars only

Object Number: 810074  Size: A2

With the key in the ignition switch, you can turn it to four different positions.

LOCK (A): This is the only position from which you can remove the key. This position locks your steering wheel, ignition and automatic transmission.

If you have an automatic transmission, the ignition switch can't be turned to LOCK unless the shift lever is in PARK (P).

Caution: On manual transmission vehicles, turning the key to LOCK/OFF will lock the steering column and result in a loss of ability to steer the vehicle. This could cause a collision. If you need to turn the engine off while the vehicle is moving, turn the key only to ACC/ACCESSORY. Do not push the key in while the vehicle is moving.

Notice: Using a tool to force the key from the ignition switch could cause damage or break the key. Use the correct key and turn the key only with your hand. Make sure the key is all the way in. If it is, turn the steering wheel left and right while you turn the key hard. If none of this works, then your vehicle needs service.

ACC (ACCESSORY) (B): This is the position in which you can operate your electrical accessories or items plugged into the accessory power outlets. It also unlocks the steering wheel and ignition. Use this position if your vehicle must be pushed or towed.

ON (C):  This is the position that the switch returns to after you start your engine and release the switch. The switch stays in ON while the engine is running. But even while the engine is not running, you can use ON to operate your electrical accessories and to display some instrument panel cluster warning and indicator lights.

START (D): This is the position that starts the engine. When the engine starts, release the key. The ignition switch will return to ON for normal driving.

When the engine is not running, ACC and ON allow you to operate your electrical accessories, such as the radio or items plugged into the accessory power outlets.

A warning tone will sound if you open the driver's door while the ignition is in ACC or LOCK and the key is in the ignition.