GM Service Manual Online
For 1990-2009 cars only

Due to its variable displacement feature, special caution is necessary when diagnosing insufficient cooling conditions with the V-5 compressor. It is normal for liquid refrigerant to collect in the compressor crankcase during extended periods of shutdown, therefore, cooling action may be delayed up to 2 minutes until the refrigerant is pumped from the compressor crankcase.

Perform the following procedure if there is a delay in cooling upon start-up beyond 2 minutes, and the normal service manual operating procedure for the A/C compressor clutch and the electrical engine cooling fan operation has been accomplished:

  1. Select the NORM A/C position.
  2. Select the high blower position.
  3. Ensure that the A/C compressor clutch is engaged.
  4. Ensure that the electrical engine is operating.
  5. Ensure that the A/C is operating.
  6. Idle the engine for 2 minutes.
  7. Perform the following procedure if there is no cooling:
  8. 7.1. Operate the engine at approximately 3,000 rotations per minute (rpm) for 1 minute.
    7.2. Ensure that the engine is idling.
    7.3. Select the mode control to the VENT position for 1 minute.
  9. Set the A/C system back to NORM A/C mode.
  10. Ensure that the A/C system is operating.
  11. Run the engine at approximately 3,000 rpm for 1 minute.
  12. Perform the following procedure if there is no cooling:
  13. 11.1. Ensure that the A/C system is operating.
    11.2. Drive the vehicle in a normal manner for 5 minutes.
    11.3. Inspect the A/C system for normal operation. If there is no cooling, refer to VDOT Air Conditioning (A/C) System Diagnosis .