GM Service Manual Online
For 1990-2009 cars only

HVAC Module Assembly Replacement LHD

Tools Required

Electronic Leak Detector.

Removal Procedure

    Caution: Refer to Safety Glasses Caution in the Preface section.

  1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
  2. Disconnect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection .
  3. Drain the cooling system. Refer to Cooling System Draining and Filling .
  4. Remove the instrument panel (I/P) pad. Refer to Instrument Panel Upper Trim Pad Replacement
  5. Remove the instrument panel carrier. Refer to Instrument Panel Carrier Replacement
  6. Remove the instrument panel centre support bracket. Refer to Instrument Panel Retainer Replacement .
  7. Disconnect the HVAC module assembly electrical connector.

  8. Object Number: 1950865  Size: SH
  9. Mark and remove the heater hoses (1) from the heater core pipes.
  10. Remove the suction hose from the thermal expansion valve. Refer to Suction Hose Replacement .

  11. Object Number: 1955612  Size: SH
  12. Remove the three HVAC mounting screws (1) in the engine bay.

  13. Object Number: 1955622  Size: SH
  14. Remove the HVAC module assembly mounting screws (1) in the cabin.
  15. Remove the HVAC module assembly from the vehicle.

Installation Procedure

    Important: Ensure the drain pipe docks with the drain assembly.

  1. Install the HVAC module assembly to the vehicle.
  2. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1955612  Size: SH
  3. Install the screws from inside the vehicle which secure the HVAC module assembly.
  4. Tighten
    Tighten the nuts to 9N·m (80 lb in).


    Object Number: 1955622  Size: SH
  5. Install the screws from the engine compartment which secure the HVAC module assembly.
  6. Tighten
    Tighten the nuts to 7N·m (62 lb in).

  7. Install the suction hose to the thermal expansion valve. Refer to Suction Hose Replacement .

  8. Object Number: 1950865  Size: SH
  9. Install the heater hoses to the heater core pipes.
  10. Install the instrument panel support bracket. Refer to Instrument Panel Retainer Replacement
  11. Install the instrument panel carrier. Refer to Instrument Panel Carrier Replacement
  12. Install the instrument panel (I/P) pad. Refer to Instrument Panel Upper Trim Pad Replacement
  13. Connect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection .
  14. Fill the cooling system. Refer to Cooling System Draining and Filling .
  15. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
  16. Leak test the fittings of the component using electronic leak detector.

HVAC Module Assembly Replacement RHD

Tools Required

    • J 38185 Hose Clamp Pliers
    • J 39400 Halogen Leak Detector

Removal Procedure

    Caution: Refer to Safety Glasses Caution in the Preface section.

  1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .
  2. Disconnect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection .
  3. Remove the engine cover. Refer to Engine Cover Replacement in Engine Mechanical - 3.6L or Engine Cover Replacement Engine Mechanical - 6.0L
  4. Drain the cooling system. Refer to Cooling System Draining and Filling .

  5. Object Number: 1955657  Size: SH

    Important: Mark position of heater hoses (3) and heater hose retaining clamps (1) before removal to make sure of correct alignment during assembly.

  6. Using J 38185 compress the heater hose retaining clamps (1) and slide 50 mm (2 in) along the heater hose (3).
  7. Remove the heater hoses (3) from the heater core pipes (2).

  8. Object Number: 1949686  Size: SH
  9. Remove the exhaust manifold heat shield to air box retaining clips (2).
  10. Remove the exhaust manifold heat shield (1).

  11. Object Number: 1950842  Size: SH
  12. Remove the insulation panel to air box retaining clips (2).
  13. Remove the insulation panel (1) from the engine compartment.

  14. Object Number: 1958686  Size: SH
  15. Remove the remote battery positive post cover (1).

  16. Object Number: 1958688  Size: SH
  17. Remove the remote battery positive post to wiring harness retaining bolt (1).
  18. Remove the starter motor power cable (2) and position aside.

  19. Object Number: 1957871  Size: SH
  20. Remove the suction pipe upper to suction pipe lower retaining nut (1).

  21. Object Number: 1955641  Size: SH
  22. Remove the suction pipe/liquid pipe retaining clip to left front chassis rail retaining bolt (3).
  23. Detach the liquid pipe (1) from the suction pipe/liquid pipe retaining clip (2).

  24. Object Number: 1950845  Size: SH
  25. Disconnect the suction pipe upper (1) from the suction pipe lower (2).
  26. Important: The sealing washer (3) is a single use item and must be discarded after use.

  27. Remove the sealing washer (3). Refer to Sealing Washer Replacement .
  28. Discard the sealing washer

    Important: Cover any opening of the A/C system with a suitable cap or tape immediately, to prevent absorption of moisture from the atmosphere.

  29. Cap or plug the suction pipe upper (1) and the suction pipe lower (2).

  30. Object Number: 1950848  Size: SH
  31. Remove the suction pipe/liquid pipe pad to thermal expansion (TX) valve retaining nut (1).

  32. Object Number: 1950850  Size: SH
  33. Disconnect the suction pipe/liquid pipe pad (3) from the TX valve (1).
  34. Important: The sealing washers (2) are a single use item and must be discarded after use.

  35. Remove the sealing washers (2). Refer to Sealing Washer Replacement .
  36. Discard the sealing washers

    Important: Cover any opening of the A/C system with a suitable cap or tape immediately, to prevent absorption of moisture from the atmosphere.

  37. Cap or plug the suction pipe (4), liquid pipe (5) and the TX valve (1).

  38. Object Number: 1950908  Size: SH
  39. Remove the HVAC module assembly to bulkhead retaining bolts (1).
  40. Remove the I/P centre support bracket. Refer to Instrument Panel Retainer Replacement .
  41. Remove the I/P upper trim pad. Refer to Instrument Panel Upper Trim Pad Replacement

  42. Object Number: 1950878  Size: SH
  43. Remove the HVAC module assembly to vehicle body retaining screws (1).
  44. Remove the I/P carrier. Refer to Instrument Panel Carrier Replacement
  45. Important: To remove the HVAC module assembly from the vehicle move the HVAC module assembly towards the back of the car off the drain assembly and downwards to clear locating pins from datum bracket.

  46. Remove the HVAC module assembly (3) from the vehicle body (2).

Installation Procedure


    Object Number: 1950878  Size: SH

    Important: Make sure the HVAC module assembly (3) fits into the drain assembly

  1. Install the HVAC module assembly to the vehicle (2).
  2. Install the instrument panel (I/P) carrier. Refer to Instrument Panel Carrier Replacement
  3. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the HVAC module assembly to I/P carrier retaining screws (1).
  5. Tighten
    Tighten the screws to 9 N·m.80 lb in.

  6. Install the I/P upper trim pad. Refer to Instrument Panel Upper Trim Pad Replacement
  7. Install the I/P retainer bracket. Refer to Instrument Panel Retainer Replacement .

  8. Object Number: 1950908  Size: SH
  9. Install the HVAC module assembly to bulkhead retaining bolts (1).
  10. Tighten
    Tighten the nuts to 7 N·m.62 lb in.


    Object Number: 1950850  Size: SH
  11. Remove the plugs or caps from the suction pipe (4), liquid pipe (5) and the thermal expansion (TX) valve (1).
  12. Important: DO NOT coat the NEW sealing washers (2) with oil, they must be fitted dry. The use of mineral oil will render the sealing washers (2) useless, as the sealing washers (2) WILL swell causing refrigerant to leak out.

  13. Install NEW sealing washers (2). Refer to Sealing Washer Replacement .
  14. Connect the suction pipe/liquid pipe pad (3) to the TX Valve (1).
  15. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1950848  Size: SH
  16. Install the suction pipe/liquid pipe pad to TX valve retaining nut (1).
  17. Tighten
    Tighten the nut to 22 N·m(16 lb ft).


    Object Number: 1957873  Size: SH
  18. Remove the plugs or caps from the suction pipe upper (1) and the suction pipe lower (2).
  19. Important: DO NOT coat the NEW sealing washer (3) with oil, they must be fitted dry. The use of mineral oil will render the sealing washer (3) useless, as the sealing washer (3) WILL swell causing refrigerant to leak out.

  20. Install a NEW sealing washer (3). Refer to Sealing Washer Replacement .
  21. Install the suction pipe upper (1) to the suction pipe lower (2).

  22. Object Number: 1955641  Size: SH
  23. Attach the liquid pipe (1) from the suction pipe/liquid pipe retaining clip (2).
  24. Install the suction pipe/liquid pipe retaining clip to left front chassis rail retaining bolt (3).

  25. Object Number: 1957875  Size: SH
  26. Install the suction pipe upper to suction pipe lower retaining nut (1).
  27. Tighten
    Tighten the nut to 22 N·m( 16 lb ft).


    Object Number: 1958688  Size: SH
  28. Install the starter motor positive cable (2) to the remote battery positive post.
  29. Install the remote battery positive post to wiring harness retaining bolt (1).
  30. Tighten
    Tighten the bolt to 15 N·m (11 lb ft).


    Object Number: 1958686  Size: SH

    Important: Make sure the clips on the remote battery positive post cover (1) are engaged to avoid an induced rattle condition.

  31. Install the remote battery positive post cover (1) to the remote battery positive post.

  32. Object Number: 1950842  Size: SH
  33. Install the insulation panel (1) to the left rear side engine compartment.
  34. Install the insulation panel to air box retaining clips (2).

  35. Object Number: 1949686  Size: SH
  36. Install the exhaust manifold heat shield (1).
  37. Install the exhaust manifold heat shield to air box retaining clips (2).

  38. Object Number: 1955657  Size: SH
  39. Connect the heater hoses (3) to the heater core pipes (2).
  40. Using J 38185 , slide the heater hose retaining clamps (1) back into the original position on the heater hoses (3).
  41. Connect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection .
  42. Fill the cooling system. Refer to Cooling System Draining and Filling .
  43. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging .
  44. Leak test the fittings of the component using J 39400 .
  45. Install the engine cover. Refer to Engine Cover Replacement in Engine Mechanical - 3.6L or Engine Cover Replacement Engine Mechanical - 6.0L