2010 Hummer H3 Owner's Manual - Page 221

Driving and Operating 3. Plug it into a normal, grounded 110-volt AC outlet. 9-37 Shifting Into Park { WARNING With all-wheel drive, the vehicle will be free to roll - even if the shift lever is in P (Park) - if the transfer case is in Neutral. So, be sure the transfer case is in a drive gear, four-wheel high (4H) or four-wheel low (4L) - not in Neutral. 2. Move the shift lever into P (Park) by pressing the shift lever button and moving the lever as far forward as it will go. 3. Turn the ignition key to LOCK/OFF. 4. Remove the key from the ignition. { WARNING Plugging the cord into an ungrounded outlet could cause an electrical shock. Also, the wrong kind of extension cord could overheat and cause a fire. You could be seriously injured. Plug the cord into a properly grounded three-prong 110-volt AC outlet. If the cord will not reach, use a heavy-duty three-prong extension cord rated for at least 15 amps. 4. Before starting the engine, be sure to unplug and store the cord to prevent damage. The length of time the heater should remain plugged in depends on several factors. Ask a dealer in the area where you will be parking the vehicle for the best advice on this. { WARNING It can be dangerous to get out of the vehicle if the shift lever is not fully in P (Park) with the parking brake firmly set. The vehicle can roll. If you have left the engine running, the vehicle can move suddenly. You or others could be injured. To be sure the vehicle will not move, even when you are on fairly level ground, use the steps that follow. If you are pulling a trailer, see Driving Characteristics and Towing Tips on page 9‑70. 1. Hold the brake pedal down, then set the parking brake. See Parking Brake on page 9‑51 for more information.