GM Service Manual Online
For 1990-2009 cars only

Object Number: 379607  Size: SH

The compressor is equipped with a pressure relief valve. The pressure relief valve is placed in the system for safety reasons. Under certain conditions, the refrigerant on the discharge side may exceed the designated operating pressure. In order to prevent system damage, the valve opens automatically when the high side pressure exceeds a specified amount. The following conditions may cause the valve to open:

    • A defective A/C pressure sensor
    • An inoperative electric cooling fan

Correct the condition. Replace the refrigerant oil and the refrigerant as needed.