Blower Motor: Testing and Inspection

WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, DISABLE THE AIRBAG SYSTEM BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. DISCONNECT AND ISOLATE THE BATTERY NEGATIVE (GROUND) CABLE, THEN WAIT TWO MINUTES FOR THE AIRBAG SYSTEM CAPACITOR TO DISCHARGE BEFORE PERFORMING FURTHER DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY OR DEATH.

For circuit descriptions and diagrams, refer to Air Conditioning/Heater:
- Faulty fuse (the fuse is located in the integrated power module (IPM) in the engine compartment)
- Faulty blower motor circuit wiring or wire harness connectors
- Faulty blower motor resistor or power module (depending on application)
- Faulty blower motor relay
- Faulty blower motor switch
- Faulty blower motor.

VIBRATION
Possible causes of front or rear blower motor vibration include:
- Improper blower motor mounting
- Improper blower wheel mounting
- Blower wheel out of balance or deformed
- Foreign material in blower wheel causing out of balance condition
- Blower motor faulty.

NOISE
To determine if the front or rear blower motor is the source of the noise, simply switch the front or rear blower motor from Off to On. To verify that the blower motor is the source of the noise, unplug the blower motor wire harness connector and operate the heating-A/C system. If the noise goes away, possible causes include:
- Foreign material in the HVAC housing
- Improper blower motor mounting
- Improper blower wheel mounting
- Blower motor faulty.