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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

A/C Problems, someone help please!

  • Thread starter Thread starter jduncan_69
  • Start date Start date Jul 31, 2005
J

jduncan_69

New Member
Apr 1, 2005
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Jul 31, 2005
#1
  • Jul 31, 2005
  • #1
I have had my fox for almost 2 years now and decided to get the A/C going. I just replaced the hose with the orifice tube and proceeded to charge the system with 134a and oil. Everything is working fine, until I turn the A/C off, and the compressor keeps running. I unplugged the wiring harness to the pressure switch and then the compressor kicks off. But as soon as I plug it back in it kicks on again. I did a contiunity test on the switch and it seems to be closed at all times. I had another switch that I put on it, but it did the same thing. I can mess with the harness while it is still plugged into the pressure switch and the compressor will kick off, but then it will not come back on when I turn the A/C back on, unless I turn the car off and then back on. Could I just have 2 bad switches or is there something else going on here?
 

PuterAmI

Member
Mar 29, 2003
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16
Madison, Alabama
Jul 31, 2005
#2
  • Jul 31, 2005
  • #2
Bad cabin switch.
 
J

jduncan_69

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Apr 1, 2005
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Jul 31, 2005
#3
  • Jul 31, 2005
  • #3
Ok, so is the pressure switch supposed toalways have contiunity between the two terminals when it in screwed into the dryer, and the switch controls the voltage going to it? Just tring to get a handle on how this is all supposed to work, but a bad cabin switch makes sense.
 
D

Daggar

New Member
Jul 19, 2004
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Jul 31, 2005
#4
  • Jul 31, 2005
  • #4
The pressure switch should always have continuuity between the terminals so long as there is ample pressure in the accumulator to keep the contacts closed. That is it's function. If you were critically low on coolant then the pressure switch would open up preventing the compressor from activating.
 
J

jduncan_69

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Apr 1, 2005
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Jul 31, 2005
#5
  • Jul 31, 2005
  • #5
The cabin switch was bad, just got done replacing it and everything works perfectly, thanks for your help guys!!!
 
S

slow84lx

clean it good before insertion
Jul 3, 2005
372
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63
Dallas, TX
Jul 31, 2005
#6
  • Jul 31, 2005
  • #6
Could you tell me where the Cabin Switch is and what it looks like? I am having A/C problems with my '84 and would like to check this. It was recently recharged but the compressor won't stay on. The Low Pressure Switch is good and has been checked. Acts like it isn't getting electrical signal to the compressor always. Works just like it should most of the time but then the compressor will kick off and won't come back on unless I turn it off and restart the engine.
 

PuterAmI

Member
Mar 29, 2003
513
0
16
Madison, Alabama
Aug 1, 2005
#7
  • Aug 1, 2005
  • #7
The "cabin switch" is the switch that you move to HEAT, DEFROST, NORM, etc.

For your 84, you have a slide lever that goes up and down and selects these. I guess one should call it a selector lever.
 
S

slow84lx

clean it good before insertion
Jul 3, 2005
372
180
63
Dallas, TX
Aug 1, 2005
#8
  • Aug 1, 2005
  • #8
PuterAmI said:
The "cabin switch" is the switch that you move to HEAT, DEFROST, NORM, etc.

For your 84, you have a slide lever that goes up and down and selects these. I guess one should call it a selector lever.
Click to expand...

Thanks...wasn't sure what "cabin switch" referred to. I have another one of those from an extra dash that I will swap it out with for testing.
 
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