AC off, still blows freezing air

[Russ]

Occasionally, for no obvious reason, with the climate control system "on" and the a/c turned "off", the system still blows freezing cold air. Pressing the a/c button on & off again doesn't help. Turning off the climate system and turning it back on doesn't help. Sometimes raising the temp setting to 75 or higher helps, sometimes not. The system will return to normal behavior after some random amount of time, or the next time the car is driven. It basically seems like the a/c is turning on regardless of what the head unit is telling it.

The fan speed function is working normally, so that rules out the usual bad transistor problem.

I checked the faq and archives for this particular symptom with no luck, any ideas?


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Russ
'91 black/black

[ANYTIME]

Try
this and see if it might help you.
John

[DanO]

Maybe you have an air pocket in your coolant lines? The bleeding procedure outlined in the manual is somewhat easy to do, assuming one has the proper tools (14mm socket with some extensions and flex joints or wobbles).

HTH,
DanO

[Russ]

Originally posted by DanO:
Maybe you have an air pocket in your coolant lines?

Perhaps but the air is much colder than the ambient outside air, extremely cold, colder than when the a/c is working normally. I tried the diagnostic suggested above, the unit thinks everything is hunky-dory. Intermittent problems are a PITA!

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Russ
'91 black/black

[BadCarma]

wish i had that problem, mine only blows hot

[PettittsAuto]

When the problem is happening check to see if the a/c compressor clutch is disengaging when you turn the a/c switch off. If the compressor stays engaged you could have a bad compressor clutch relay causing the compressor to run with the switch turned off. If the clutch stays engaged find the clutch relay and disconnect it and try a new relay. I have seen this problem before on other Acura products.

Bruce www.pettittsauto.com