GM Service Manual Online
For 1990-2009 cars only

Special Tools

J 39400-A Halogen Leak Detector

Removal Procedure

  1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .

  2. Object Number: 1646735  Size: SH

    Important: When removing the thermal expansion valve (TXV), keep dirt and foreign material from getting on or into the sealing surfaces. Clean tools and a clean work area are important for proper service. The TXV seal area should be cleaned before any repairs are performed. The parts must be kept clean at all times and any parts to be assembled should be cleaned with a non-petroleum based solvent and dried with air. Use only lint free cloths to wipe parts. Do not allow solvent to enter evaporator or hoses.

  3. Remove the evaporator outlet hose and liquid line retainer plate nut from the TXV.
  4. Remove the evaporator outlet hose and liquid line from the TXV.
  5. Remove and discard the sealing washers from the evaporator outlet hose and liquid line.
  6. Install protective caps to the evaporator outlet hose and the liquid line to prevent contamination and desiccant saturation. Refer to Sealing Washer Replacement .

  7. Object Number: 1646787  Size: SH
  8. Remove the TXV bolts from the backing plate.
  9. Remove the TXV and the backing plate from the vehicle.
  10. Remove and discard the seal washers from the evaporator pipes. Refer to Sealing Washer Replacement .
  11. Install a protective cap to the evaporator pipes to prevent contamination and desiccant saturation.

Installation Procedure


    Object Number: 1646787  Size: SH

    Important: Use only lint free cloths to wipe parts. Do not allow any solvent to enter evaporator or hoses.

  1. Remove the protective caps from the evaporator pipes and ensure the seal areas are clean, dry and lint free.
  2. Install new seal washers to the evaporator pipes. Refer to Sealing Washer Replacement .
  3. Remove the protective caps from the TXV.
  4. Install the TXV and the backing plate to the evaporator pipes.
  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.

  6. Install the TXV bolts to the backing plate.
  7. Tighten
    Tighten the bolts to 3.5 N·m (31 lb in).


    Object Number: 1646735  Size: SH
  8. Remove the protective caps from the liquid line and the evaporator outlet hose.
  9. Install new seal washers to the liquid line and the evaporator outlet hose. Refer to Sealing Washer Replacement .
  10. Install the liquid line and the evaporator outlet hose to the TXV.
  11. Install the liquid line and evaporator outlet hose retainer plate nut to the TXV.
  12. Tighten
    Tighten the nut to 20 N·m (15 lb ft).

  13. Evacuate and charge the A/C system. Refer to Refrigerant Recovery and Recharging .
  14. Test the affected A/C joints for leaks using J 39400-A .