GM Service Manual Online
For 1990-2009 cars only

Object Number: 1839823  Size: A3

The ignition switch has four different positions.

To shift out of P (Park), the ignition must be in ON/RUN or ACC/ACCESSORY and the brake pedal must be applied.

Notice: Using a tool to force the key to turn in the ignition could cause damage to the switch or break the key. Use the correct key, make sure it is all the way in, and turn it only with your hand. If the key cannot be turned by hand, see your dealer/retailer.

(LOCK/OFF): This position locks the ignition. It also locks the transmission. The key can only be removed in LOCK/OFF. The shift lever must be in P (Park) to turn the ignition switch to LOCK/OFF. The steering can bind with the wheels turned off center. If this happens, move the steering wheel from right to left while turning the key to ACC/ACCESSORY. If this doesn't work, the vehicle needs service.

ACC (ACC/ACCESSORY): This position lets you use things like the radio and windshield wipers while the engine is not running.

(ON/RUN): This position can be used to operate the electrical accessories and to display some instrument panel warning lights. The switch will stay in this position while 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 position starts the engine. When the engine starts, release the key. The ignition switch will return to the ON/RUN position for driving. A warning tone will sound when the driver door is opened, the ignition is in ACC/ACCESSORY or LOCK/OFF and the key is in the ignition.