Not a LS vehicale. But i am sure someone on here can help me out. I have a 99 S10 and the HVAC position selector swtich isnt working. Can somone help me out?

 

I am not sure if the s10 controls are vacuum operated but if you have a vacuum leak on your ac control line like on the ls1 cars it will default to defrost/floor only...if you can not get it to turn on or anything I would assume you need a new controller...

 

On a Firebird or Camaro that part of the control is operated by vacuum. There is a round piece behind there that has several small tubes attached and when you turn the **** the vacuum selects a different part to operate. You probably have a vacuum problem.

The fan part of your HVAC control is just an electrical switch and the hot/cold blend is cable operated.

If you can get your head down in the floor well on the passenger side see if you can hear a leak or hear the control change, with the engine running of course.