How to Use a Heater-Defroster in a 2001 GMC Sierra
- 1). Study the comfort controls panel on the dashboard. The three knobs, from left to right, control the fan, the temperature and the mode, which means the source of the air entering the cab.
- 2). Select a fan speed. To increase the fan speed, turn the dial clockwise so the indicator points to a higher number. To decrease fan speed, reverse the direction counterclockwise. To turn the fan off, move the indicator all the way to the left.
- 3). Set the temperature. The middle knob on the panel has a blue and red band around the top half that indicates temperature settings. For heat, point the indicator to the red part of the band. Try out a few settings before you settle on the best one for current weather conditions.
- 4). Choose the mode of air delivery from the options depicted on the right-hand dial with icons that show the source of where the air enters the cab in relation to the occupants. Starting at the bottom left, the first choice is vent, with airflow coming from the dashboard vents. Next, the bi-level option uses both dash and floor-level vents and the third choice points the incoming heated air directly at your feet.
The blend setting activates the defroster vents at the base of the windshield and at the side windows while still sending some warmth to your feet. The fifth choice focuses primarily on the windows. Point the indicator to the space between two icons to get a mix of the two settings.
