I have a problem with the heater of my car. The heater will not respond to any controls except the fan. I can change the modes on the display but the mode doors will not move. I can change the
temp on the display but the blend doors do not move.
I took off the battery cables and touched them together let the car sit overnight with the battery
disconnected. I reconnected the battery started the car up and none of the HVAC controls work.
I took the control head out of the 2001 SLS parts car and installed it in the 2002 sls and it does the
same thing has no actuator movement. I tested the 2001 before removing it and it seemed to work
During all this there has been no HVAC codes.
Thanks for any help, Joe
can we assume you have checked all the fuses?
particularly #33 under the back seat?
and can we assume you checked for codes using the built in scanner -
with the key ON - engine OFF -
do you hear anything at all from the havc system ?
do you hear the fan from the cabin air-temp sensor -
it's behind the small grill to the left of the steering wheel -
if you turn the temp slowly up to 90* -
does the display change - but absolutely no sound?
what if you slowly change the temp to 60* -
if you push the RECIRCULATE button - can you hear anything move -
we just had a lot of rain - and 40* -
now it is in the single digits -
was the car outside in the rain -
is the car outside now -
my thought is that all the flaps on the various control doors have frozen shut -