2012 Buick Enclave Owner's Manual - Page 273

Driving and Operating 9-19 { WARNING Turning off the vehicle while moving may cause loss of power assist in the brake and steering systems and disable the airbags. While driving, only shut the vehicle off in an emergency. If the vehicle cannot be pulled over, and must be shut off while driving, turn the ignition to ACC/ACCESSORY. 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 does not work, then the vehicle needs service. ACC (ACC/ACCESSORY): This is the position in which you can operate the electrical accessories or items plugged into the accessory power outlets. This position unlocks the ignition and steering wheel. Use this position if the vehicle must be pushed or towed. 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): R (ON/RUN): This position can be used to operate the electrical accessories and to display some instrument panel warning and indicator lights. This position can also be used for service and diagnostics, and to verify the proper operation of the malfunction indicator lamp as may be required for emission inspection purposes. The switch stays in this position when the engine is running. The transmission is also unlocked in this position. If you leave the key in the ACC/ACCESSORY or ON/RUN This is the position that starts the engine. When the engine starts, release the key. The ignition switch will return to ON/RUN for driving. Starting the Engine Move the shift lever to P (Park) or N (Neutral). The engine will not start in any other position. To restart the engine when the vehicle is already moving, use N (Neutral) only. Notice: Do not try to shift to P (Park) if the vehicle is moving. If you do, you could damage the transmission. Shift to P (Park) only when the vehicle is stopped.