Operation CHARM: Car repair manuals for everyone.

Control Assembly: Description and Operation

When the vehicle operator turns the auxiliary HVAC control switch front to the Low, Med, or High positions, power passes through the rear auxiliary HVAC control assembly and the front auxiliary HVAC control assembly controls the ground. When power is delivered to the rear auxiliary HVAC control assembly, an internal splice within the switch routes the power back out to the front auxiliary HVAC control assembly on the auxiliary blower motor speed control circuits. Ground is routed back through the rear auxiliary HVAC control assembly on the ground circuits and a splice pack to ground.