GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Caution: Refer to Battery Disconnect Caution in the Preface section.


    Object Number: 1255876  Size: SH
  1. Disconnect the negative battery cable.
  2. Remove the heating and ventilation systems control assembly. Refer to Heater and Air Conditioning Control Replacement .
  3. Disconnect the small connector to the vacuum control switch on the rear of the assembly case.
  4. Separate the control assembly case halves.
  5. Turn the bulb holder to the left and pull out the bulb.

Installation Procedure


    Object Number: 1255877  Size: SH
  1. Install the bulb into the holder and turn the bulb to the right.
  2. Install the control assembly case halves.
  3. • Pass the connector for the vacuum switch through the hole in the rear assembly case part.
    • Be sure to align the flat mating control shafs of 2 case halves.
  4. Install the connector into the vacuum control switch.

  5. Object Number: 1255878  Size: SH
  6. Install the control assembly. Refer to Heater and Air Conditioning Control Replacement .
  7. Connect the negative battery cable.
  8. Check the knob light for proper operation.