2010 Chevrolet Impala Owner's Manual - Page 126

Ignition Positions The ignition switch has four different positions. A (LOCK/OFF): This position locks the ignition. It also locks the transmission. This is the only position in which the ignition key can be inserted or removed. The steering can bind with the wheels turned off center. If this happens, move the steering wheel from left to right while turning the key to ACC/ACCESSORY. If this doesn't work, then the vehicle needs service. B (ACC/ACCESSORY): This is the position in which you can operate the radio and windshield wipers while the engine is off. To use ACC/ACCESSORY, turn the key clockwise. C (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. To shift out of P (Park), the ignition must be in ON/RUN 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. 3-20