GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 39529 Heater Hose Pliers

Removal Procedure

  1. Drain the engine coolant. Refer to Cooling System Draining and Filling in Engine Cooling.
  2. Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement in Engine Control.
  3. Recovery the refrigerant from the A/C system. Refer to Refrigerant Recovery and Recharging in Heating, Ventilation and Air Conditioning.
  4. Remove the accumulator. Refer to Air Conditioning Accumulator Replacement in Heating, Ventilation and Air Conditioning.

  5. Object Number: 301617  Size: SH
  6. Remove the hose clamps from the outlet hose and the inlet hose using the J 39529 .
  7. Disconnect the vacuum line from the bypass valve.

  8. Object Number: 301596  Size: SH
  9. Remove the heater inlet hose and the outlet hose from the bypass valve.
  10. Remove the bypass valve (3) from the vehicle.

Installation Procedure


    Object Number: 301596  Size: SH
  1. Install the bypass valve (3) to the vehicle.
  2. Connect the heater inlet hose and the outlet hose to the bypass valve (5).

  3. Object Number: 301617  Size: SH
  4. Install the hose clamps using the J 39529 .
  5. Connect the vacuum line to the bypass valve.
  6. Install the accumulator. Refer to Air Conditioning Accumulator Replacement in Heating, Ventilation and Air Conditioning.
  7. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging in Heating, Ventilation and Air Conditioning.
  8. Fill the engine coolant. Refer to Cooling System Draining and Filling in Engine Cooling.