For 1990-2009 cars

1. Remove the instrument panel storage compartment (Pontiac only). Refer to Instrument Panel Storage Compartment Replacement in Instrument Panel, Gauges and Console.
2. Remove the temperature valve link rod (1) from the temperature valve by snapping the rod out of the valve.
3. Start the vehicle. Make the following settings:

• | Set the fan to position IIII (HIGH).

• | Set the temperature to full hot.

4. Allow 45 seconds minimum for the A/C temperature valve actuator (4) to move to the full hot position.
5. Move the temperature valve to the full hot position.
6. Snap the temperature valve link rod into the temperature valve.