DEFINITION: Diagnosing the source of noise coming from the blower motor.

1. Inspect the heater ducts for obstructions.
2. Clean the ducts as needed.
3. Inspect the heater case for obstructions.
4. Clean as needed.

Has the noise stopped?

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System OK

Go to Step 2

Remove the blower motor. Refer to Blower Motor and Fan Replacement .

Is there debris in the blower housing?

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Go to Step 3

Go to Step 4

Clean the housing.

Has the noise stopped?

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System OK

Go to Step 4

Replace the blower motor. Refer to Blower Motor and Fan Replacement .

Are the repairs complete?

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Go to Step 5

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Has the noise stopped?

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System OK

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