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Electrical AC only blows through defrost

  • Thread starter Thread starter red5.0fox
  • Start date Start date Jul 6, 2022

red5.0fox

Active Member
Dec 1, 2019
190
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38
Hope Mills, North Carolina
Jul 6, 2022
#1
  • Jul 6, 2022
  • #1
I know there are many threads on this already and I’ve read a lot of them and everything seems to check out. I’ve checked the vacuum tree and the AC line, all the way to the check valve, and even to the reservoir in the fender. I’ve also taken out the glove box and checked the AC connections back there. I did find that the black vacuum line behind the glove box WAS disconnected. But even after reconnecting it, the issue still persists. I’ve also pulled out the ac controls to make sure nothing is unplugged there and it’s all good. Hopefully someone here has any ideas?
 

KRUISR

10 Year Member
Apr 16, 2015
1,802
903
143
Jul 6, 2022
#2
  • Jul 6, 2022
  • #2
I am assuming that heat only comes out the defrost as well. I would look at the check valve in the engine compartment - passenger side. If it is not working right you won't have vacuum for the actuators.
 

red5.0fox

Active Member
Dec 1, 2019
190
25
38
Hope Mills, North Carolina
Jul 6, 2022
#3
  • Jul 6, 2022
  • #3
KRUISR said:
I am assuming that heat only comes out the defrost as well. I would look at the check valve in the engine compartment - passenger side. If it is not working right you won't have vacuum for the actuators.
Click to expand...
So I can’t believe this just happened. I had already checked the check valve, made sure everything was getting vacuum (which it was) then you made this reply and for the hell of it I did the exact same thing again. I took off the vac lines on the valve and made sure vacuum was being received, plugged it back, and my vents started blowing. I’m honestly confused as hell lol. Crazy.
 

KRUISR

10 Year Member
Apr 16, 2015
1,802
903
143
Jul 6, 2022
#4
  • Jul 6, 2022
  • #4
You may want to source a new one to have ready if it quits again.
 
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