GM Service Manual Online
For 1990-2009 cars only

Engine Coolant Heater Description

The optional engine coolant heater (RPO KO5) is designed to warm the coolant in the engine block area for improved starting in very cold weather (-29°C/-20°F). The coolant heater helps reduce fuel consumption when a cold engine is warming up. The engine coolant heater is rated at 600 watts. The engine coolant heater operates using 110 volt AC external power and a heating element installed in the water jacket of the engine block. The heating element warms the coolant when the heater cord plugs into the AC power source.

The unit is equipped with a detachable AC power cord.