No heat /// just cold

gl boy

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Any suggestions ? Please ,,,
The heater system on my 2007 cl 500 is only blowing cold and freezing air even when on highest heat temperature
, thanks in advance
 

E55BOF

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Sounds most likely to be a flap motor problem to me. Unless you already have a good diagnostic reader like an iCarsoft which can read the data stream, best get the car to an indie for a STAR diagnosis.
 

markjay

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Does the engine reach operating temperature (80-90)? If not, then the thermostat may need replacing.

Also, the valve that controls the coolant flow to the heater matrix in the cabin might be stuck shut, or the electronics that control it failed.
 

Smiley

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If no hot air from any vents then likely cause is the heater valve, also known as a duo valve. Gets corroded inside and stops working. Usually located in the engine bay near the bulkhead.
 
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gl boy

gl boy

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Thanks guys , jumped in it tonight , it’s working perfectly , gremlins are work I think , thanks for your input thought guys , appreciate your words
 

Smiley

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With colder weather coming it might be worth seeing if there are any stored codes at least you'll know what needs fixing if it happens again. If it is the valve starting to play up then it's a matter of when, not if, the problem recurs. The good news is that the valves are not expensive, changing it out is easy - the question is how much dismantling is needed on your car to get to it.
 

E55BOF

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If it's cured itself it's more likely the heater valve than a flap problem.
 

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