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No voltage at A/C clutch connector

  • Thread starter Thread starter blackcloud50
  • Start date Start date Dec 18, 2005
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blackcloud50

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Mar 30, 2005
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Dec 18, 2005
#1
  • Dec 18, 2005
  • #1
Turned on a/c today and idle speed did not go up so I checked for voltage at the a/c clutch connector and there is none. The fuse is also good.
 
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PRO50SC

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Dec 28, 2003
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Olney, Maryland
Dec 18, 2005
#2
  • Dec 18, 2005
  • #2
Check for voltage at the switch on the accumulator. If it's there, jump it and see if the clutch fiers. If it does, it's either low on freon or the switch is bad.

If there is no power at the switch, then you'll have to trace it down.
 
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blackcloud50

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Dec 18, 2005
#3
  • Dec 18, 2005
  • #3
PRO50SC said:
Check for voltage at the switch on the accumulator. If it's there, jump it and see if the clutch fiers. If it does, it's either low on freon or the switch is bad.

If there is no power at the switch, then you'll have to trace it down.
Click to expand...

There is definitely no freon in the system. Condensor had been replaced and a/c lines have were disconnected in the past and was never recharged but I thought I should still see voltage.

Since system is empty will I see voltage at the accumulator connector anyway but not at compressor connector?
 
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PRO50SC

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Dec 28, 2003
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Dec 18, 2005
#4
  • Dec 18, 2005
  • #4
blackcloud50 said:
There is definitely no freon in the system. Condensor had been replaced and a/c lines have were disconnected in the past and was never recharged but I thought I should still see voltage.

Since system is empty will I see voltage at the accumulator connector anyway but not at compressor connector?
Click to expand...
You should follow the instructions in my previous post!
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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Dec 18, 2005
#5
  • Dec 18, 2005
  • #5
If the system is empty, DONT jump the wiring. A lack of lube in there is not good. I am not sure if Bernie might not have seen that your system was evacuated, or perhaps I am just too cautious.

FWIW, juice goes from the LPS to the WOT relay, and that relay is known for burning its wires. Once you get the system filled, and if it still wont energize, check those wires. The WOT relay is on the pass fender, kinda under the inlet tube.

Good luck.
 
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blackcloud50

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Mar 30, 2005
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Dec 18, 2005
#6
  • Dec 18, 2005
  • #6
PRO50SC said:
You should follow the instructions in my previous post!
Click to expand...

will do
 
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blackcloud50

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Mar 30, 2005
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Dec 21, 2005
#7
  • Dec 21, 2005
  • #7
PRO50SC said:
Check for voltage at the switch on the accumulator. If it's there, jump it and see if the clutch fiers. If it does, it's either low on freon or the switch is bad.

If there is no power at the switch, then you'll have to trace it down.
Click to expand...

Well I do have voltage at the connector for the pressure switch on the accumulator.
I did not verify if the switch or compressor is bad at this point but I assume that because the system has no freon that is why the compressor doesn't come on like you mentioned.

My main concern was making sure that I had voltage from the computer for the a/c. i know the wiring is fine (main engine harness) because it is brand new.

Thanks
 

Black1987Stang

Active Member
Aug 22, 2004
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Jersey Shore
Dec 22, 2005
#8
  • Dec 22, 2005
  • #8
HISSIN50 said:
FWIW, juice goes from the LPS to the WOT relay, and that relay is known for burning its wires.

Good luck.
Click to expand...

So thats why all my wires are burned to a crisp
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Dec 22, 2005
#9
  • Dec 22, 2005
  • #9
87stangdiddle said:
So thats why all my wires are burned to a crisp
Click to expand...
Yep. And I in rereading this, what I said sounds misleading. The relay itself has nothing to do with the wires' insulation vulcanizing - it is the heat in that area that vulcanizes the wiring.

I just wanted to say something so peeps dont think it is an actual electrical issue (it is a heat issue).
 

PuterAmI

Member
Mar 29, 2003
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Madison, Alabama
Dec 22, 2005
#10
  • Dec 22, 2005
  • #10
blackcloud50 said:
Well I do have voltage at the connector for the pressure switch on the accumulator.
I did not verify if the switch or compressor is bad at this point but I assume that because the system has no freon that is why the compressor doesn't come on like you mentioned.

My main concern was making sure that I had voltage from the computer for the a/c. i know the wiring is fine (main engine harness) because it is brand new.

Thanks
Click to expand...

Yep, it is. You can jumper the connector for a second or so to see if the compressor kicks on. Won't damage it for just the few seconds.

It takes 25 or more PSI (stock R12 system) to engage the LPCS. Anything less and you will not get voltage at your compressor.
For more info on your system, see the below webpage.

http://knology.net/~puter/carpics/r134a.html
 
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