2003 GMC Sonoma Owner's Manual - Page 94

A (ACCESSORY): This position lets you use things like the radio and the windshield wipers when the engine is off. Push in the key and turn it toward you. Your steering wheel will remain locked, just as it was before you inserted the key. B (LOCK): This position locks your ignition, steering wheel and transmission. It's a theft-deterrent feature. You will only be able to remove your key when the ignition is turned to LOCK. C (OFF): This position lets you turn off the engine but still turn the steering wheel. Use OFF if you must have your vehicle in motion while the engine is off (for example, if your vehicle is being towed). D (RUN): This is the position for driving. On manual transmission vehicles, turning the key to LOCK 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 engineoff while the vehicle is moving, turn the key onlyto OFF. Don't press the key release button while the vehicleis moving. E (START): This position starts your engine. Nofice: If your key seems stuck in LOCK and you can't turn it, be sure you are using the correct key; if so, is it all the way in? If it is, then turn the steering wheel left and right while you turn the key hard. Turn the key only with your hand. Using a tool to force it could break the key or the ignition switch. If none of this works, then your vehicle needs service. 2-19