2009 Hummer H3T Owner's Manual - Page 83

Features and Controls 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. (D) START: This is the position that starts the engine. When the engine starts, release the key. The ignition switch returns to ON/RUN 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. 2-17 Retained Accessory Power (RAP) These vehicle accessories can be used for up to 20 minutes after the engine is turned off: Starting the Engine Place the transmission in the proper gear. Automatic Transmission Move the shift lever to P (Park) or N (Neutral). The engine will not start in any other position. To restart the vehicle when it 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. Manual Transmission The shift lever should be in N (Neutral) and the parking brake engaged. Hold the clutch pedal down to the floor and start the engine. The vehicle will not start if the clutch pedal is not all the way down. Audio System Front Wipers Power Windows Sunroof (if equipped) These features will work when the key is in ON/RUN or ACC/ACCESSORY. Once the key is turned from ON/RUN to LOCK/OFF, these features continue working for up to 20 minutes or until a door is opened.