Removal Procedure

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Remove the right rear quarter trim panel.
Refer to TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (UTILITY) or TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (SUBURBAN) in INTERIOR TRIM .
Disconnect the electrical connectors (3,4) from the auxiliary HVAC control module (1).
Remove the screws from the auxiliary HVAC control module (1).
Remove the auxiliary HVAC control module (1) from the auxiliary HVAC module (2).

Fig 1: Removing HVAC Control Module - Auxiliary
Courtesy of GENERAL MOTORS CORP.