HVAC Control Components: Off
WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
When the OFF position is selected, the HVAC control module applies voltage to the fan off input within the HVAC control module through the off blower motor control circuit. When the HVAC control module receives this input, any A/C request will be cancelled and the A/C request LED will turn off. Fresh air will still be brought in from the outside, but the LED indicator on the switch will not illuminate.