Just pulled the transmission to replace the rear main. Started the car and the head unit showed 3 dashes the fan was blowing on high and there was no change by pushing any of the buttons. Turned it off checked fluid levels and made sure everything was alright. restarted it and the ac seemed to be working fine. Drove it 8 or 10 times (about 400 miles). Then the 3 dashes came back and it is stuck in that mode. Any ideas what could have caused it to do this?

It'* some sort of communication error between the HVAC unit and the PCM. It does the same thing every time I have my tuner connected to the car.

It did this a couple years ago when I had a bad wire in the fuel tank to the pump. Seemed crazy that the fuel pump could affect the climate control but when I fixed the fuel pump wire the climate control started working fine. I will follow the wire from the PCM to the programmer and see what I find.

Took your advice Mike and started looking for an electric problem. Removed the pass side hush cover and started to remove the connector to the programmer. I noticed pretty quick that wiggling the conector would make the display come on intermittantly.. Took it apart and loked for obvioius problems.. No dirt , no corrosion.. put a little dielectric grease on it and put it back together. Seems to be working now. Got my fingers crossed.

Good deal. Keep us posted!

It'* been 3 months and it is working like a charm!

Thanks!