2013 Buick LaCrosse Owner Manual - Page 220

9-18 Driving and Operating ventilation fan and 12-volt power outlet, as well as to display some 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 transmission is also unlocked in this position. The battery could be drained if the key is left in the ACC/ACCESSORY or ON/RUN position with the engine off. The vehicle might not restart if the battery is allowed to drain for an extended period of time. 4 (START): This position starts the engine. When the engine starts, release the key. The ignition switch will return to ON/RUN for normal driving. A warning tone sounds when the driver door is opened when the ignition is still in ACC/ACCESSORY and the key is in the ignition. If the ignition becomes difficult to turn, see Keys on page 2‑1. 4. Set the parking brake. See Parking Brake on page 9‑32. Key Lock Release { 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. 2 (ACC/ACCESSORY): This position provides power to some of the electrical accessories. It unlocks the ignition. To move the key from ACC/ACCESSORY to LOCK/OFF, the shift lever must be in P (Park). 3 (ON/RUN): The ignition switch stays in this position when the engine is running. This position can be used to operate the electrical accessories, including the Vehicles with an automatic transmission are equipped with an electronic key lock release system. This system is to prevent ignition key removal unless the shift lever is in P (Park).