Been searching the interweb for about an hour trying to figure out what the circled lever does on my heater control! Any oppo wisdom out there tonight? On the left side of the slide theres a side profile outline of a car with an arrow going straight into where the windshield meets the hood and then goes horizontal once in the car and on the right side there is the same side profile outline with the arrow going in a fat oval around the inside of the car. Ive seen it in other cars before and never figured out what it does, when I push it to the right the blows gets a bit louder but thats about all I can make of it.