GM Service Manual Online
For 1990-2009 cars only

The following conditions indicate that the electrical circuits are functioning properly:

    • The air conditioning operates at all speeds in any position except for OFF
    • The A/C compressor clutch engages

The system is charged properly if the hand-felt temperatures of the following components are the same:

    • The A/C evaporator inlet pipe
    • The A/C receiver/dryer or dehydrator surface of an opening system

The air conditioning control head is operating correctly when the air conditioning control head distributes air from the designed outlets.