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Automatic air system correct?
The heat only works if you put it to 85, if you put it lower it blows cold correct?
Yes, That's correct, I'm not sure about the AC, I'll try to run it and find out now
I'm not sure about the AC - it blows cold, but not sure if it mixes heat or not as outside temp is about 78* and it's hard to tell
Most of the time when that happens and the head doesn't work properly, it's due to the sun load sensor.
How handy are you?
Hang on and I will get you the steps to perform self diag on the auto air system.
Give me a min
Click HERE to download the self diag steps and code listings.
Once you performed these steps, you will get a code. The code will indicate where the fault is on the system.
Most common for your description is the Sun Load sensor
Give it a try and see what you come up with.