GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2003 🢒 Impala 🢒 HVAC 🢒 Heating, Ventilation and Air Conditioning 🢒 Defroster Door Replacement

Removal Procedure

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

  1. Disconnect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  2. Remove the IP lower trim panel. Refer to Instrument Panel Lower Trim Panel Replacement in Instrument Panel, Gages, and Console.
  3. Remove the steering column. Refer to Steering Column Replacement in Steering Wheel and Column.
  4. Disconnect the left side fuse block from the cross vehicle beam.

    5. Object Number: 812951 Size: SH
  5. Remove the retaining screw (1) from the panel air duct.
  6. Remove the bolts from the panel air duct.
  7. Remove the panel air duct from the cross vehicle beam.

    8. Object Number: 507699 Size: SH
  8. Remove the retaining bolts from the right air duct.
  9. Remove the right air duct from the cross vehicle beam.
  10. Remove the passenger knee bolster bracket. Refer to Passenger Knee Bolster Bracket Replacement in Instrument Panel, Gages, and Console.
  11. Position the body control module away from the cross vehicle beam.
  12. Disconnect any ground wires, as necessary.
  13. Remove the brake pedal. Refer to Brake Pedal Assembly Replacement in Hydraulic Brakes.
  14. Remove the 3 bolts from the brake pedal bracket to cross vehicle beam.
  15. Release the wiring harness retaining clips from the cross vehicle beam and position the wiring harness aside.

    16. Object Number: 558111 Size: SH
  16. Remove the bolts from the HVAC module center support.
  17. Remove the bracket from the HVAC module center support.
  18. Reposition the vacuum harness.

    19. Object Number: 558113 Size: SH
  19. Remove the bracket bolts from the HVAC module upper support.

    20. Object Number: 812572 Size: SH
  20. Remove the bolts from the right and left side of the cross vehicle beam.

    21. Object Number: 558194 Size: SH
  21. Remove the cross vehicle beam.

    22. Object Number: 708587 Size: SH
  22. Disconnect the two vacuum lines from the defroster actuator (3).
  23. Disconnect the orange vacuum line from the recirculation actuator and install a hand vacuum pump (2).
  24. Remove the defroster actuator from its attachment to the HVAC module case.
  25. Using the hand vacuum pump (2) open the recirculation actuator door.
  26. Rotate the defroster actuator to the right and up into the opening between the back of the dash and the opening into the HVAC module. The opening which results when the recirculation actuator door is in the full open position.
  27. Disconnect the defroster actuator from the defroster door arm.

    28. Object Number: 607130 Size: SH
  28. Remove the retaining screws (1) to the air distribution case cover.
  29. Remove the air distribution case cover (2).
  30. Remove and discard the air distribution case seal.
  31. Remove the linkage between the defroster door and the vent door on the left side of the HVAC module assembly.

    32. Object Number: 607136 Size: SH
  32. Remove the defroster door (1).

Installation Procedure

    Object Number: 607136 Size: SH

    Important: Align the defroster door assist spring to the HVAC module assembly case.

  1. Install the defroster door (1).
  2. Connect the linkage between the defroster door and the vent door.
  3. Install a new air distribution case seal.

    4. Object Number: 607130 Size: SH
  4. Install the air distribution case cover (2).

    5. 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.

  5. Install the retaining screws (1) to the air distributor cover.

    6. Tighten
    Tighten the screws to 1.5 N·m (13 lb in).


    Object Number: 708587 Size: SH
  6. Connect the orange vacuum line to a hand vacuum pump (2).
  7. Using the hand vacuum pump (2) open the recirculation actuator door.
  8. Rotate the defroster actuator to the right and up into the opening between the back of the dash and the opening into the HVAC module. The opening which results when the recirculation actuator door is in the full open position.
  9. Connect the defroster actuator to the defroster door arm.
  10. Position the defroster actuator on to the mounting slides of the HVAC module assembly.
  11. Ensure that the lock tab locks the defroster actuator in place.
  12. Connect the vacuum lines to the defroster actuator.
  13. Connect the vacuum line to the recirculation actuator.

    14. Object Number: 558194 Size: SH
  14. Install the cross vehicle beam to the vehicle.

    15. Object Number: 812572 Size: SH
  15. Install the bolts to the right and left side of the cross vehicle beam.
  16. Tighten the bolts to the right and left side of the cross vehicle beam in sequence.

    17. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).


    Object Number: 558113 Size: SH
  17. Install the bracket bolts to the HVAC module upper support.

    18. Tighten
    Tighten the bolts to 10 N·m (89 lb in).

  18. Install the passenger knee bolster bracket. Refer to Passenger Knee Bolster Bracket Replacement in Instrument Panel, Gages, and Console.

    19. Object Number: 558111 Size: SH
  19. Install the bracket to the HVAC module center support.
  20. Reposition the vacuum harness to the original position.
  21. Install the bracket bolts to the HVAC module center support.
  22. Tighten the bracket bolts in sequence as shown.

    23. Tighten
    Tighten the bolts to 10 N·m (89 lb in).

  23. Reposition the IP wiring harness to the cross vehicle beam and secure the retaining clips.
  24. Install the 3 bolts through the brake pedal bracket to the cross vehicle beam.

    25. Tighten
    Tighten the bolts to 50 N·m (37 lb ft).

  25. Install the brake pedal. Refer to Brake Pedal Assembly Replacement in Hydraulic Brakes.
  26. Connect all disconnected ground wires.
  27. Reposition the body control module in place.
  28. Install the fuse blocks to the cross vehicle beam.

    29. Object Number: 507699 Size: SH
  29. Install the right air duct to the cross vehicle beam.
  30. Install the right air duct bolts.

    31. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 812951 Size: SH
  31. Install the panel air duct to the cross vehicle veam.
  32. Install the panel air duct screw (1).

    33. Tighten
    Tighten the bolts to 1.8 N·m (16 lb in).

  33. Install the panel air duct bolts.

    34. Tighten
    Tighten the bolts to 10 N·m (89 lb in).

  34. Install the steering column. Refer to Steering Column Replacement in Steering Wheel and Column.
  35. Install the lower trim panel. Refer to Instrument Panel Lower Trim Panel Replacement in Instrument Panel, Gages, and Console.
  36. Connect the battery negative cable.