GM Service Manual Online
For 1990-2009 cars only

Relays and Sensors

The compressor is equipped with a pressure relief valve. The valve is placed in the system as a mechanical safety device. Under certain conditions, refrigerant pressure on the compressor discharge side may exceed the designed operating level. The valve is designed to open automatically at approximately 3654 ±483   kPa (530 ±69 psi).

This open valve performs the following functions:

    • Prevents system damage.
    • Vents the refrigerant to the atmosphere.

Correct any condition that causes this valve to open.