GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

The mode valve actuator is located on the top left side of the heater/vent module.

  1. Remove the knee bolster. Refer to Knee Bolster Replacement in Instrument Panel, Gauges, and Console.

  2. Object Number: 515031  Size: SH
  3. Remove the right side driver knee bolster bracket (2) from the steering column bracket (1) and the intermediate bracket (3).

  4. Object Number: 394104  Size: SH
  5. Disconnect the vacuum connectors (1) from the mode actuator (5).
  6. Remove the actuator rod retaining clip (4).
  7. Remove the actuator rod (2) from the mode valve lever (3).

  8. Object Number: 394087  Size: SH
  9. Firmly pull on the mode actuator in order to remove the actuator from the heater/vent module.

Installation Procedure


    Object Number: 394087  Size: SH
  1. Install the mode actuator. Ensure that the retaining tab locks into place.

  2. Object Number: 394104  Size: SH
  3. Install the actuator rod (2) to the mode valve lever (3).
  4. Install the actuator rod retaining clip (4).
  5. Connect the vacuum connectors (1) to the mode actuator (5).

  6. Object Number: 515031  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  7. Install the right side driver knee bolster bracket (2) to the steering column bracket (1) and the intermediate bracket (3).
  8. Tighten

        • Tighten the knee bolster bracket mounting nuts to 5.5 N·m (49 lb in).
        • Tighten the intermediate bracket mounting bolts (4) to 10 N·m (88 lb in).
  9. Install the knee bolster. Refer to Knee Bolster Replacement in Instrument Panel, Gauges, and Console.