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HELP AC Clutch wont kick in

B

bbfanatic23

New member
Well, I'll get right to it. A couple weeks ago I went to recharge the AC System but it would not take any freon and the gages didn't move. I then noticed that the AC Clutch was not kicking in. And when I Tested the Power going to it I got nothing. Someone mentioned that it might be a bad pressure switch, but I'm clueless. Any ideas???
 


im no a/c pro but that does sound right. if you run power to the green wire on the plug to the compressor it should engage and then work.

this is not meant to fix it, just to test the compressor, its power comes from that pressure switch i believe.
 
My wife's compressor wouldn't kick on a month or two ago. Stuck a gauge on it and put a can of R134 or whatever in it and it's been good for the last few months.

Might just be low on refrigerant.
 
buck531 said:
My wife's compressor wouldn't kick on a month or two ago. Stuck a gauge on it and put a can of R134 or whatever in it and it's been good for the last few months.

Might just be low on refrigerant.
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Same thing for me, the clutch has a pressure valve on it that won't allow it to engage unless there is enough freon in your system. Applying power to it basically overrides that fail safe.
 
Yeah. Whatever prevents the clutch from actuating when the pressure is not high enough. You'll hear it if you fill your system up with r134a and if your AC is "running". It will suddenly click on and you'll hear your engine increase it's load, you don't have to watch it. Also, your fans should start spinning faster to move more air across the radiator and AC condenser.
 


Oh I see. Sorry nevermind . They are different. Any idea where the pressure SWITCH is located. And whether it would the high or low I would need to change out?
 
Ok, so I tested the clutch straight from the battery and got the clutch to click on, thus confirming that it works. I then replaced the high side ac switch. Hooked up the gages and started the car but the clutch would not kick on. I started out with no freon and maybe got 1/4 of R134A into the system and with that both low and high side gages read 110. Still nothing from the AC Clutch. So i tested the clutch, replaced the ac switch, put in 110psi worth of R134A freon, checked fuses and tested relays. So I guess my clutch is not getting any voltage, what would cause it to not turn on?
 
Low side switch is the one that needs looked at not the high side (if it's out of refrigerant)...Also have you done any other work on the car recently? Is your IAT sensor unplugged or failed?
 


I also checked the Iat sensor and it shows to be good after testing it with a multimeter. The system did take a little refrigerant but was empty. Also checked the power going away from ac compressor for any shorts.
 


I replaced them both, but one at time, as they went bad at different times in the last 6 months or so(first one got replaced because a snake found it to be a nice home). They don't turn on when i turn the ac on, but only once my car has reached 200ish degrees. Seems like a faulty thermostat to me when it comes to that problem. And I'm not 100% sure but I dont think the fans come on when I jumped the AC Compressor today.
 
ok just checking if it was bad wires or a sensor.

when the a/c is on, the fans should come on. maybe whats not sending power to the compressor's also not powering the fans.
 
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