Mechanics

HEAT WILL NOT TURN OFF

1980 Cadillac Fleetwood • 72,000 miles

Previous owner said heat will not turn off so he bypassed the heater core. I want heat for winter so I want this car back to original. What could be wrong with the car that the heat will not turn off? Could this be the climate control switch ora relay?
Does bypassing the heater core do damage?
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HHTS
November 2, 2013.




No bypassing the heater core doesnt' damage anything. Due to age of your vehicle we dont' have much info available. You have auto temp control so have a mechanic see if he can get the control head to see what is wrong with it. I thin you hit off an d defrost buttons at same time for it to diagnose itself to see what is wrong.


Hmac300
Nov 2, 2013.
It doesn't have a digital climate control. I uploaded a picture of what is there.
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Tiny
HHTS
Nov 3, 2013.
Ture but it's auto temp control these are a bear for someone inexperienced. The manual also doesn't cover heat won't shut off so i'm sending instructions on how to check for no eec meaning it doesn't light up also check all your vacuum lines for leaks as well as connections. Also check the water valve on engine to see if it closes with a/c on that could be the problem as well. It shold have vacuum an dit shold be colder thant the input line.


Hmac300
Nov 3, 2013.
I did some more checking and found that the blower motor does not turn off. What would cause that?


Tiny
HHTS
Nov 9, 2013.
This car is over 30 years old, I am taking a huge guess on this as I personally have not worked on one of these in ages. Either the programmer is bad or a component in it or the ground to it. Or the blower motor circuit board. Seepics


Hmac300
Nov 9, 2013.

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