The temperature control on my 1998 supercab doesn't work. I changed the potentiometer thinking that was the problem. Does anyone know why I can't get either the ac to regulate or the heat to blow hot? Is there some other circuit I need to check?

 

well my 97 had a poor connection between the fuse and the fuse box and it caused teh ac blend door, cruise and power mirrors not to work. Check that. Of course if you already changed teh potentiometer you probably checked simple things like fuses.

 

Check to see if you here a hissing sound by the temp control?
If so you have a vaccum hose leek behind that pnl.

 

My symptoms:

I have blown 4 potentiometers in around 10K miles. It's not that they're blown electrically, but that after awhile the potentiometer loses all physical resistance and it I can't change the temperature. Every time I replace the potentiometer, it fixes for awhile and then dies again.

Called the service manager at the local Ford dealer, he has never heard of this before. I was about to buy just a standard rheostat and solder it in there, but the NAPA guy said that was a bad idea. Something about it could blow the blend door motor. He also suggested checking the motor and the potentiometer and seeing if there was a short somewhere seeing as those are the only things in the circuit.

Has anyone else out there had this issue; and better yet, fixed it? Any help would greatly be appreciated

 

In the future, do not revive ancient posts and do not post multiple times in different threads for the same issue.

Steve

 

Sorry Steve

I assumed it was better to use less storage space on an old thread than force a whole new database on what was a simple problem

Fixed it with glue anyways