Test Description

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The numbers below refer to the step numbers on the diagnostic table.

2. This step tests for auxiliary blower motor operation in any speed setting.
8. This step determines if the malfunction is in the control side of the system.
10. Test both the rear auxiliary HVAC control assembly chassis ground circuit and the ground circuit between the front and rear HVAC control assemblies.

Fig 1: Diagnosis Procedure Blower Motor Inoperative - Auxiliary (Step 1 To 8)
Courtesy of GENERAL MOTORS CORP.

Fig 2: Diagnosis Procedure Blower Motor Inoperative - Auxiliary (Step 9 To 21)
Courtesy of GENERAL MOTORS CORP.