Operation CHARM: Car repair manuals for everyone.

A/C Blower Motor Speed Control

CAUTION: The system should not be operated with the blower motor disconnected. Damage may occur to the A/C blower motor speed control if cooling air is not provided by the blower motor.




The A/C blower motor speed control, located in the A/C evaporator case, converts low current signals from the electronic control assembly to a high current, variable ground feed to the blower motor. A delay function provides a gradual increase or decrease in blower motor speeds in all conditions. In addition, there is a high blower relay integral with the blower speed controller which provides power for maximum airflow in the high blower position.