I have a 98 Millenia S in excellent shape. The A/C & heater runs great, but the Auto Climate Control does not work, it just blows the A/C at full blast all the time. When I press the Ambient temp botton it reads 99 F, so I assume it blows full blast b/c it never thinks it is getting any cooler. Any ideas anyone? Is there a ambient cabin temp sensor I can replace? Other than the Auto function all else works great. I'm just using it like a normal A/C for the time being.

 

so if you turn off the auto function, every thing works....
it does sound like an issue with the ambient temp sensor circut.
that unit has a self diagnostic function, i'll try to look it up
are there any aftermarket accessories installed inside the vehicle??
radio, alarm....amps...

 

Thanks for your help, there are no aftermarket items, every thing is stock. I'm going to stop by the local Mazda dealer today and see what input they have. If they come up with anything I'll be sure to post it.

 

I downloaded a manual for a 96 model I have a 2000 and a lot of the electronics where the same. the web site is "http://rapidshare.com/files/51248650/Millenia-1996.rar".. On pages U22-U25 it shows you how to reset the c/c system. If that don't work try taking the negative cable off of the battery while it's running for 2 or 3 minutes, this rests a lot of computers back to default. Good Luck!

 

i would bet the cc amp is hosed. get one off ebay for about 30 bucks. easy to change, that part of the dash just pops out, 2 screws, one on each side of the steering wheel, then CAREFULLY pry off the dash. it will come out just enough for you to reach behind and disconnect the wiring harness', then it all comes out. cc amp/assy is attached to the part of the dash that you pull out. takes about 30 min on a bad day.