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A/C problems, need suggestions...

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Old Mar 12, 2012 | 09:36 AM
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Default A/C problems, need suggestions...

So my A/C went out and I am trying to diagnose what is broken.

Currently, the compressor won't kick on when I press the A/C button or the Recycle Air button, but the fan speed works fine, it's just ambient air that comes out. I jumped the low pressure sensor with a wire, and it still didn't come on. The belt on the compressor is spinning, but the clutch just won't engage. Checked the A/C fuse already, are there others I should check?

I already have another compressor I picked up from a member on here for cheap, but I would rather not replace it if that's not the problem.

Thoughts of ways I can diagnose this myself?
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Old Mar 12, 2012 | 08:28 PM
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Did you check the relay in the fuse box as well..was there alot of noise before it quit working or did it just quit all of a sudden?
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Old Mar 13, 2012 | 09:09 AM
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Noticed one day that the a/c wasn't blowing cold, popped the hood and saw that the compressor clutch was engaging and disengaging for a few seconds at a time with the a/c button depressed. Then after a few days, the compressor wouldn't engage at all.

I probably should have included that description to begin with, but forgot about it until you mentioned something.
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Old Mar 13, 2012 | 10:13 AM
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I would rule out the clutch coil first by checking for voltage at the pigtail. If its getting voltage but not engaging you know its the coil and you might as well swap the compressor.
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Old Mar 13, 2012 | 10:39 AM
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Originally Posted by Robert91RS
I would rule out the clutch coil first by checking for voltage at the pigtail. If its getting voltage but not engaging you know its the coil and you might as well swap the compressor.
That is a fantastic idea! Wish I had thought of that

Thanks for the help
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Old Mar 13, 2012 | 11:25 AM
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What about having auto climate and having the a/c work-clutch engage when using that, but when you hit the a/c button it no longer engages and works. Anybody got any ideas on that...? The a/c is controlled by two different trigger possibilities right..?
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Old Mar 13, 2012 | 04:13 PM
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Originally Posted by Robert91RS
I would rule out the clutch coil first by checking for voltage at the pigtail. If its getting voltage but not engaging you know its the coil and you might as well swap the compressor.
I just remembered that I switched out the A/C relay with a relay that I was sure worked (fuel pump iirc) and no change. Would that be the same as testing the voltage at the pigtail?
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Old Mar 13, 2012 | 04:14 PM
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Just move to Alaska & roll your window down.
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Old Mar 13, 2012 | 04:17 PM
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Originally Posted by AKlowriderZ71
Just move to Alaska & roll your window down.
My A/C went out in October or November, so that's pretty much what I've been doing this whole time, but now summer is approaching
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Old Mar 13, 2012 | 04:50 PM
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Originally Posted by TX Tahoe Z71
I just remembered that I switched out the A/C relay with a relay that I was sure worked (fuel pump iirc) and no change. Would that be the same as testing the voltage at the pigtail?
No, you really want to confirm voltage at the coil when possible.
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