DEFINITION: Noise originating from the blower motor.

Were you sent here from the HVAC Symptoms?

Go to Step 2

Go to Symptoms - HVAC Systems - Manual in HVAC Systems - Manual

1. Sit inside the vehicle.
2. Close the vehicle doors and windows.
3. Turn ON the ignition, with the engine OFF.
4. Cycle the blower motor through all of the speeds and modes in order to determine where and when the noise occurs.

Is a noise evident during the blower operation?

Go to Step 3

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Does the noise vary with the blower speed?

Go to Step 4

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Inspect for excessive vibration at each blower motor speed by feeling the blower case.

Is excessive vibration present?

Go to Step 5

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Remove the blower motor. Refer to Blower Motor Replacement .

Inspect the blower motor for deposits of foreign material.

Is there foreign material on the blower motor?

Go to Step 7

Go to Step 6

Inspect the blower motor for the following:

1. Cracked blades
2. Loose impeller retainer
3. Improper impeller alignment

Were any of these conditions found?

Go to Step 8

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Remove the foreign material.

Is the action complete?

Go to Step 9

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Replace the blower motor. Refer to Blower Motor Replacement .

Is the replacement complete?

Go to Step 9

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Operate the system in order to verify the repair.

Did you find and correct the condition?

System OK

Go to Step 2