1994 Pontiac Bonneville Owner's Manual - Page 56

To Use the Coolant Heater: 1. Turn off the engine. NOTICE: After you've used the coolant heater, be sure to 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 weather, the kind of oil you have, and some other things. Instead of trying to list everything here, we ask that you contact a Pontiac dealer in the area where you'll be parking your vehicle. The dealer can give you the best advice for that particular area. 2. Open the hood and unwrap the electrical cord., 3. Plug it into a normal, grounded 110-volt outlet. 1 Engine Coolant Heater (Engine Block Heater) (OPTION) In very cold weather, 0" F (- 18O 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 minimum of four hours prior to starting your vehicle. 55.D.