'03 auto air con responds at 90 degrees only

[punkieys17]

The auto air con is responding to the temeprature control at 90 degrees only. Above 90 degrees it heats uncontrollably, at 89 or lower it cools without stopping.

There appears to be no finesse to the control, and on full auto will keep heating or freezing without a stop - any idea which bits I should be checking please?

Julian

 

[jrneyman]

could be a faulty control panel; maybe a blend door actuator, which opens and closes automatically to blend the air to the proper temperature--

id go for a haynes manual on this one---

anybody else??? ideas???