GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2004 🢒 LeSabre 🢒 HVAC 🢒 Heating, Ventilation and Air Conditioning 🢒 HVAC Module Assembly Replacement
    • J 38185 Hose Clamp Pliers
    • J 39400-A Halogen Leak Detector

Removal Procedure
  1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
  2. Drain the coolant. Refer to Cooling System Draining and Filling in Engine Cooling.

    3. Object Number: 419227 Size: SH
  3. Remove the evaporator hose nut from the evaporator.
  4. Remove the evaporator hose from the evaporator.
  5. Remove and discard the sealing washers from the evaporator hose. Refer to Sealing Washer Replacement .

    6. Object Number: 419273 Size: SH
  6. Remove the heater hoses from the heater core using the J 38185 .
  7. Plug the heater core and evaporator openings to prevent leaking into the vehicle when the HVAC module is removed.
  8. Remove the instrument panel assembly. Refer to Instrument Panel Carrier Replacement in Instrument Panel, Gages and Console.

    9. Object Number: 419272 Size: SH
  9. Remove the defroster duct screws (1,2).
  10. Remove the defroster duct nut (3).
  11. Remove the defroster duct.
  12. Remove the air distributor duct screws.
  13. Remove the air distributor duct.

    14. Object Number: 419246 Size: SH
  14. Disconnect the blower control module (1) connector.
  15. Disconnect the instrument panel to HVAC module (2) connector.

    16. Object Number: 247142 Size: SH
  16. Remove the HVAC module retaining nuts (1-5).
  17. Remove the HVAC module.

Installation Procedure

    Object Number: 247142 Size: SH
  1. Install the HVAC module.

    2. 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.

    Important: Refer to the illustration for the HVAC module fastener torque sequence.

  2. Install the HVAC module nuts to the dash (1-5).

    3. Tighten
    Tighten the nuts in sequence (1-5) to 9 N·m (80 lb in).


    Object Number: 419246 Size: SH
  3. Install the blower control module (1) connector.
  4. Install the I/P harness to HVAC module connector (2).
  5. Install the defroster duct.

    6. Object Number: 419272 Size: SH
  6. Install the defroster duct module mounting screws (1,2).

    7. Tighten
    Tighten the screws to 1.4 N·m (12 lb in).

  7. Install the defroster duct mounting nut (3) to the front of dash.

    8. Tighten
    Tighten the nut to 9 N·m (80 lb in).

  8. Install the air distributor duct.
  9. Install the air distributor duct screws.

    10. Tighten
    Tighten the screws to 1.4 N·m (12 lb in).

  10. Install the I/P assembly. Refer to Instrument Panel Carrier Replacement in Instrument Panel, Gages and Console.

    11. Object Number: 419273 Size: SH
  11. Install the heater hoses to the heater core using the J 38185 .
  12. Install new sealing washers to the evaporator hose. Refer to Sealing Washer Replacement .

    13. Object Number: 419227 Size: SH
  13. Install the evaporator hose to the evaporator.
  14. Install the evaporator hose nut.

    15. Tighten
    Tighten the nut to 20 N·m (15 lb ft).

  15. Recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
  16. Leak test the fittings using the J 39400-A .
  17. Fill the engine coolant. Refer to Cooling System Draining and Filling in Engine Cooling.