Grand Cherokee 2WD V8-5.2L VIN Y (1998)
Blower Motor: Component Tests and General Diagnostics
Blower Motor Testing and Inspection
For additional blower motor testing and inspection refer to: "Computers and Control Systems : Body Control Module : Testing and Inspection"
See: Body and Frame/Body Control Systems/Body Control Module
Blower Motor Diagnosis and Testing
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, REFER TO AIRBAGS SYSTEMS BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIR-BAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.
BLOWER MOTOR
Possible causes of an inoperative blower motor include:
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Faulty fuse
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Faulty blower motor ground circuit wiring or connectors
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Faulty blower motor resistor (manual temperature control)
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Faulty blower motor power module (ATC)
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Faulty blower motor switch
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Faulty heater-A/C mode control switch
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Faulty blower motor feed circuit wiring or connectors
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Faulty blower motor.
Possible causes of the blower motor not operating in all speeds include:
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Faulty fuse
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Faulty blower motor switch
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Faulty blower motor resistor (manual temperature control)
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Faulty blower motor power module (ATC)
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Faulty high speed blower motor relay (ATC)
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Faulty ATC controller
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Faulty blower motor circuit wiring or connectors.
Blower Motor Noise and Vibration Diagnosis
VIBRATION
Possible causes of blower motor vibration include:
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Improper blower motor mounting
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Improper blower wheel mounting
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Blower wheel out of balance or bent
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Blower motor faulty.
Blower Motor Electrical Diagnosis
NOISE
To verify that the blower is the source of the noise, disconnect the blower motor connector and operate the heater-A/C system. If the noise goes away,
possible causes include:
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Foreign material in the heater-A/C housing Improper blower motor mounting
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Improper blower wheel mounting Blower motor faulty.
