GM Service Manual Online
For 1990-2009 cars only

Air Conditioning Evaporator Thermal Expansion Valve Replacement RHD

Tools Required

J 39400 Halogen Leak Detector

Removal Procedure

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

  1. Remove the radiator air baffle and deflector. Refer to Radiator Air Upper Baffle and Deflector Replacement.
  2. Remove the engine cover. Refer to Engine Cover Replacement for 3.6L engine, or Engine Cover Replacement for 6.0L engine.
  3. Recover the refrigerant Refer to Refrigerant Recovery and Recharging.
  4. Disconnect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection.
  5. Remove windscreen wiper arms. Refer to Windshield Wiper Arm Replacement.
  6. Remove the air inlet grill panel. Refer to Air Inlet Grille Panel Replacement.
  7. Remove the air filter assembly. Refer to Air Cleaner Assembly Replacement for 3.6L engine, or Air Cleaner Assembly Replacement for 6.0L engine.

  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 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: 1950873  Size: SH

    Important: Using a suitable tool, unscrew the TX valve to evaporator pad retaining hex screws (1).

  39. Remove the TX valve to evaporator pad retaining screws (1).
  40. Important: Reinstall the suction pipe/liquid pipe to TX valve retaining nut to assist in the removal of the TX valve.

  41. Reinstall the suction pipe/liquid pipe to TX valve retaining nut (2).

  42. Object Number: 1955649  Size: SH

    Important: Place the TX Valve in a plastic bag to avoid any contamination from air born dirt or moisture.

  43. Remove the TX valve (3) from the evaporator pad (1).
  44. Important: The sealing washers (2) are a single use item and must be discarded after use.

  45. Remove the sealing washers (2) from the evaporator pad (1). Refer to Sealing Washer Replacement .
  46. 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.

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

Installation Procedure


    Object Number: 1955649  Size: SH
  1. Remove the plugs or caps from the thermal expansion (TX) valve (3) and the evaporator pad (1).
  2. 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.

  3. Install NEW sealing washers (2) to the evaporator pad (1). Refer to Sealing Washer Replacement .
  4. Connect the TX valve (3) to the evaporator pad (1).

  5. Object Number: 1950850  Size: SH
  6. Remove the plugs or caps from the suction pipe (4), liquid pipe (5) and the TX valve (1).
  7. 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.

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


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


    Object Number: 1957873  Size: SH
  13. Remove the plugs or caps from the suction pipe upper (1) and the suction pipe lower (2).
  14. 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.

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

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

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


    Object Number: 1958688  Size: SH
  23. Install the starter motor positive cable (2) to the remote battery positive post.
  24. Install the remote battery positive post to wiring harness retaining bolt (1).
  25. 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.

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

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

  30. Object Number: 1949686  Size: SH
  31. Install the exhaust manifold heat shield (1).
  32. Install the exhaust manifold heat shield to air box retaining clips (2).

  33. Object Number: 1955646  Size: SH
  34. Attach the suction pipe (2) and the liquid pipe (3) from the suction pipe/liquid pipe retaining clip (1).
  35. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging.
  36. Install the radiator air baffle and deflector. . Refer to Radiator Air Upper Baffle and Deflector Replacement.
  37. Install the air filter assembly. Refer to Air Cleaner Assembly Replacement for 3.6L engine, or Air Cleaner Assembly Replacement for 6.0L engine.
  38. Install the engine cover. Refer to Engine Cover Replacement for 3.6L engine, or Engine Cover Replacement for 6.0L engine.
  39. Install the plenum chamber cover panel. Refer to Air Inlet Grille Panel Replacement.
  40. Install the windscreen wiper arms. Refer to Windshield Wiper Arm Replacement.
  41. Connect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection.
  42. Leak test the fittings of the component using J 39400 .