2003 GMC Savana Van Owner's Manual - Page 106

Engine Coolant Heater In very cold weather, 0°F (-18°C) or colder, the engine coolant heater can help. You'll get easier starting and better fuel economy during engine warm-up. Usually, the coolant heater should be plugged in a f minimum o four hours prior to starting your vehicle. At temperatures above 32°F (OOC), use of the coolant heater is not required. PI ,ging the cord to an ungrouI.-.td --.tlet 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 won't reach, use a heavy-duty three-prong extension cord rated for at least 15 amps... To Use the Engine Coolant Heater 1. Turn off the engine. 2. Open the hood and unwrap the electrical cord. The cord for the engine coolant heater is located on the driver's side of the engine compartment and is attached to the hose for the power steering reservoir. 3. Plug it into a normal, grounded 1 10-volt AC outlet. 4. Before starting the engine, be sure to unplug and store the cord as it was before to keep it away from moving engine parts. If you don't, it could be damaged. How long should you keep the coolant heater plugged in? The answer depends on the outside temperature, the kind of oil you have, and some other things. Instead of trying to list everything here, we ask that you contact your dealer in the area where you'll be parking your vehicle. The dealer can give you the best advice for that particular area. 2-23