Operation CHARM: Car repair manuals for everyone.

Blower Motor Malfunction

TEST DESCRIPTION

Steps 1-7:




Steps 8-14:




The numbers below refer to the step numbers on the diagnostic table.
2. This step will determine if one or more blower speeds are inoperative.
4. This step determines if the HVAC control module (IPM) and blower motor control processor are attempting to control the blower motor speed.
6. The measured voltage on the blower speed control circuit should steadily decrease from 4.7 V to 0.65 V as the blower speed is adjusted from the minimum speed position to the maximum speed position.