I have a 2001 SLS. The main problem I am having is that once the AC is on, it will not auto or manually switch to heat. I can pull over and set it to heat, shut the car off, restart it, and then the heat will work. Once I have heat working, if I turn the temp down, it will switch back to AC but I would have to shut the car off again to get it to go to back to heat. Both heat and AC work but it is the electronic switching between the two that seems to have the issue. Has anyone experienced this or have any solutions?

 

If you are trying to have a/c blow out at floor; system is not designed to do that. If control head is set at 60 (max cold) air will only blow out dash vents if set at 65 air will shift as interior temp gets closer to 65. If this is not the case; the HVAC system will set DTC related to system failures, but you will need scanner to read them.

 

Thanks for reply. If I have the temp set on, lets say 70°, the ac blows from vents and works fine. If I turn it up to 80°, the draft doors will switch to floor but I never get hot air it will only blow cold air. If I pull over and shut the car off, turn the car back on, I will then get hot air.

 

I think you will need a Tech2 to figure it out. There was a software update in 2006 which I would think would have already been done. You could try to reset actuators by disconnecting battery for at least 60 seconds. Myself I would wait 2 minutes. See it that solves problem.