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A/C help.

Messages
40
Likes
6
Location
Ferndale, Washington, USA
#1
No A/C clutch engagement. Ok...so push ac button led turns on, radiator fan starts and engine idle changes but no cold air. With engine off LP side a/c hose is around 70PSI so refrigerant is good. The 10 amp fuse is good and has vbat across it, relay operates correctly by closing circuit and am getting vbat sent through closed circuit. So I'm getting voltage out of the relay but not sure if the voltage is making it all the way to clutch as the plug is a pain to get at and probe. Before I try to get access to it my question is if the wiring goes through any other sensors after it leaves the relay or does that all happen before. I know there are a few sensors that work with the A/C but don't know where down the line they come into play. If the sensors act on the clutch engagement BEFORE the fuse and relay then I know all criteria is good and it's either the wiring to the clutch or at the clutch as I'm getting vbat out of the relay

Does anyone have the wiring diagram for the AC clutch circuit?

I got the car used with front end damage and the ambient temp sensor was not working so that was replaced and is now working.
 


Messages
72
Likes
42
Location
Tucson
#3
No A/C clutch engagement. Ok...so push ac button led turns on, radiator fan starts and engine idle changes but no cold air. With engine off LP side a/c hose is around 70PSI so refrigerant is good. The 10 amp fuse is good and has vbat across it, relay operates correctly by closing circuit and am getting vbat sent through closed circuit. So I'm getting voltage out of the relay but not sure if the voltage is making it all the way to clutch as the plug is a pain to get at and probe. Before I try to get access to it my question is if the wiring goes through any other sensors after it leaves the relay or does that all happen before. I know there are a few sensors that work with the A/C but don't know where down the line they come into play. If the sensors act on the clutch engagement BEFORE the fuse and relay then I know all criteria is good and it's either the wiring to the clutch or at the clutch as I'm getting vbat out of the relay

Does anyone have the wiring diagram for the AC clutch circuit?

I got the car used with front end damage and the ambient temp sensor was not working so that was replaced and is now working.
AAT sensor and the picture from sir Sprinkle (evap temp sensor) do have a factor in it, check and advise as necessary. Aside from that, no other wiring from the clutch relay besides the clutch itself. I'd check power and ground at the connector and go from there as much as it is a pain to get to. Could be a broken wire from the prior accident.
 


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PunkST

2000 Post Club
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2,239
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1,413
Location
Menasha
#4
Following this as i also dont have A/C from a deer strike.
 


PunkST

2000 Post Club
Messages
2,239
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1,413
Location
Menasha
#5
Any updates on this?? Its getting extremely warm out. And being a welder by trade makes me need AC on the drive home.
 


OP
G
Messages
40
Likes
6
Location
Ferndale, Washington, USA
Thread Starter #6
I AM getting vbat to the compressor so its gota be a bad coil at this point. @spedy7 any chance you could look up a part number for the clutch coil? Can't seem to find it anywhere saw a youtube video and coil had part # CYH5F but don't see that part number being sold anywhere.
 


Last edited:

PunkST

2000 Post Club
Messages
2,239
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1,413
Location
Menasha
#7
Can the coil just be replaced? Or do you habe to get a whole new compressor?.
 


OP
G
Messages
40
Likes
6
Location
Ferndale, Washington, USA
Thread Starter #8
I deleted my last response because i couldn't find the coil and figured i had to replace the whole piece, but i found a non oem one on ebay for $53 but they don't state a part number and I can't find any schematic that offers an oem coil only so im going to just order the ebay coil and see what happens.
 


Last edited:
Messages
72
Likes
42
Location
Tucson
#9
Just a tech so can't get any parts numbers, unfortunately. I'd recommend ohming out the ground too, just to be on the safe side. Replacing the coil also requires a special tool to hold the clutch in place while removing the whole assembly, Rotunda tool #412-134. Could fab one up too if you're crafty.
 


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