2007 Hummer H3 Owner's Manual - Page 103

The battery could be drained if you leave the key in the ignition while your vehicle is parked. You may not be able to start your vehicle after it has been parked for an extended period of time. Automatic Transmission Move your shift lever to PARK (P) or NEUTRAL (N). Your engine will not start in any other position -- this is a safety feature. To restart when you are already moving, use NEUTRAL (N) only. Notice: Do not try to shift to PARK (P) if your vehicle is moving. If you do, you could damage the transmission. Shift to PARK (P) only when your vehicle is stopped. Retained Accessory Power (RAP) Your vehicle has Retained Accessory Power (RAP) which allows certain features of your vehicle to continue working for up to 20 minutes after the ignition key is turned to LOCK. The radio, front wipers, power windows, and a sunroof if your vehicle has one, will work when the ignition key is in ON or ACC. Once the key is turned from ON to LOCK, these features continue working for up to 20 minutes or until a door is opened. Manual Transmission The shift lever should be in the NEUTRAL position and the parking brake engaged. Hold the clutch pedal to the floor and start the engine. Your vehicle will not start if the clutch pedal is not all the way down. That is a safety feature. Starting the Engine Place the transmission in the proper gear. Starting Procedure 1. With your foot off the accelerator pedal, turn the ignition key to START. When the engine starts, let go of the key. The idle speed will go down as the engine gets warm. Do not race the engine immediately after starting it. Operate the engine and transmission gently to allow the oil to warm up and lubricate all moving parts. 103