A/C knobs not working, air not flowing from dashboard vents
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Joined: Sep 2003
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From: Raleigh, NC
A/C ***** not working, air not flowing from dashboard vents Ok, I've done some searches on this. Seen a variety of answers, so I figured I'd ask here.
Recently, the **** that switches from A/C to defrost to floor/dashboard mode, etc has quit working. The detents that it used to have are gone and the **** just turns throughout it's arc of travel without any resistance. As a result, the HVAC only blows on the floor vents and the A/C will not engage. The ***** that control the temp from hot to cold and the fan settings still work fine.
A/C system was overhauled and compressor replaced in the last 2 years, so that's not the problem.
Is this indicative of the common vacuum line HVAC problem or does the problem more likely reside directly behind my dash panel?
Recently, the **** that switches from A/C to defrost to floor/dashboard mode, etc has quit working. The detents that it used to have are gone and the **** just turns throughout it's arc of travel without any resistance. As a result, the HVAC only blows on the floor vents and the A/C will not engage. The ***** that control the temp from hot to cold and the fan settings still work fine.
A/C system was overhauled and compressor replaced in the last 2 years, so that's not the problem.
Is this indicative of the common vacuum line HVAC problem or does the problem more likely reside directly behind my dash panel?
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Joined: Dec 2010
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From: Maricopa, AZ
A/C ***** not working, air not flowing from dashboard vents Ok, I've done some searches on this. Seen a variety of answers, so I figured I'd ask here.
Recently, the **** that switches from A/C to defrost to floor/dashboard mode, etc has quit working. The detents that it used to have are gone and the **** just turns throughout it's arc of travel without any resistance. As a result, the HVAC only blows on the floor vents and the A/C will not engage. The ***** that control the temp from hot to cold and the fan settings still work fine.
A/C system was overhauled and compressor replaced in the last 2 years, so that's not the problem.
Is this indicative of the common vacuum line HVAC problem or does the problem more likely reside directly behind my dash panel?
Recently, the **** that switches from A/C to defrost to floor/dashboard mode, etc has quit working. The detents that it used to have are gone and the **** just turns throughout it's arc of travel without any resistance. As a result, the HVAC only blows on the floor vents and the A/C will not engage. The ***** that control the temp from hot to cold and the fan settings still work fine.
A/C system was overhauled and compressor replaced in the last 2 years, so that's not the problem.
Is this indicative of the common vacuum line HVAC problem or does the problem more likely reside directly behind my dash panel?
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Joined: Sep 2014
Posts: 321
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From: Fort Wayne, IN
Ok, I've done some searches on this. Seen a variety of answers, so I figured I'd ask here.
Recently, the **** that switches from A/C to defrost to floor/dashboard mode, etc has quit working. The detents that it used to have are gone and the **** just turns throughout it's arc of travel without any resistance. As a result, the HVAC only blows on the floor vents and the A/C will not engage. The ***** that control the temp from hot to cold and the fan settings still work fine.
A/C system was overhauled and compressor replaced in the last 2 years, so that's not the problem.
Is this indicative of the common vacuum line HVAC problem or does the problem more likely reside directly behind my dash panel?
Recently, the **** that switches from A/C to defrost to floor/dashboard mode, etc has quit working. The detents that it used to have are gone and the **** just turns throughout it's arc of travel without any resistance. As a result, the HVAC only blows on the floor vents and the A/C will not engage. The ***** that control the temp from hot to cold and the fan settings still work fine.
A/C system was overhauled and compressor replaced in the last 2 years, so that's not the problem.
Is this indicative of the common vacuum line HVAC problem or does the problem more likely reside directly behind my dash panel?
http://shbox.com/1/vac_check_valve.jpg
Last edited by CamOnlyJabroni; Aug 4, 2015 at 07:20 AM.
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From: Little Rock, AR
Thread Starter
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From: Raleigh, NC
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From: Little Rock, AR
You should still be able to feel the detents when moving the switch from position to position.
IIRC the vaccume supply Tees in above the passangers side manifold. There is also a check valve. That is were I would start after the broken knobb. My **** on my 02 will split every couple years and I have to glue it.
