GM Service Manual Online
For 1990-2009 cars only

Scan Tool Method

Refer to the scan tool user manual for more information on how to clear DTCs in the heater-A/C control.

Ignition Cycle Default

If no Diagnostic Trouble Codes (DTCs) occur for 100 drive cycles (a drive cycle occurs when the ignition switch is turned to the on position and the vehicle is driven faster than 16 km/h (10 mph), any existing DTCs are automatically cleared form the heater-A/C control.