GM Service Manual Online
For 1990-2009 cars only

As an aid in determining whether or not the following are operating properly, refer to the System Performance table:

    • The air conditioning (A/C)
    • Electrical
    • Air
    • The refrigeration systems
  1. The operation of the air conditioning (A/C) blower at all 4 speeds, in any position except the OFF position, and the engagement of the compressor clutch indicate that the electrical circuits are functioning properly.
  2. The operation of the A/C control selector and the distribution of air from the designated outlets indicates proper functioning.

Object Number: 106095  Size: SF
(1)Upper Mode
(2)Bi-Level Mode
(3)Lower Mode
(4)Defog Mode
(5)Defrost Mode

Cold and Hot Air Test

With the mode knob in DEFROST, the temp knob in HOT, and the fan switch in HIGH, temperature from the defroster outlet should be above the temperature outside of the vehicle.