Autoheat problem

[rydingk]

I have an 82 SC with autoheat.

The theremister works giving an ohm reading consistent with heat. the hotter it gets the less the reading.

However, the autoheat unit when turned on always go to full heat. theree is no halfway or adjustment for temperature.
All of there parts of the heating system works perfectly.

My mechanic thinks that it may be a resister on the autoheat's board (dry joint)

Does anyone have any ideas?
Many thanks
Keith

[David Goodman]

Keith,
There is a temperature sensor that the factory calls a Caloric Feeler that runs from the temperature control to the left hand heater (flapper) box. The part has gone bad creating an open circuit which causes the heat lever to raise all the way and stay there. I priced out the part some time back and it was big $$$ from the dealer. The business end is also riveted to the heater box so it will be a little work to replace. Hope this helps,
Dave

I'll try and find a picture to post

[David Goodman]

[rydingk]

Dave
What I need to do is isolate the problem that i have with the autoheat.
So if you could tell me how to test each component. Caleric feeler, thermistor and autoheat unit I would be grateful.
K

[David Goodman]

Keith,
I'll post the temp sensor specs when I return from work but what were the results of the first set of troubleshooting steps that were outlined in our PMs.

What was the resistance across the two leads of the Caloric Feeler, with the car warmed up, at the point where it plugs into the console ?

What happened when you bridged the two leads that the caloric feeler plugs into with the resistor ? (ignition key on, dial set to position 1)
Dave