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Old Jun 21, 2010 | 01:02 PM
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Last summer my A/C gradually began blowing from cold to cool to warm air. I left it for the winter and figured I'd deal with it now.

I bought the r-134a can from autozone and went to hook it up today, but it seems like my compressor isn't kicking on so it wont take the charge.

Also when I hooked the pressure gauge up to the low side valve, the needle doesn't budge. Is that normal to have no pressure with the compressor off?

Or is the compressor not turning on because there's no pressure?

Need some help with this one guys. What should I be checking?
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Old Jun 21, 2010 | 01:34 PM
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Sounds like it was completely empty and the pressure switch is keeping the compressor off. If there's referigerant in the system from what you added you should be getting some pressure even with the car off now? I'd try adding another can, system holds 1.5 lbs.
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Old Jun 21, 2010 | 01:35 PM
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My chilton book says to pull the low-pressure cycling switch plug from the evaporator inlet line and attach a jumper wire across the terminals to turn the compressor on.

Where can I find this?
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Old Jun 21, 2010 | 02:05 PM
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Originally Posted by 2001NBMZ28
Sounds like it was completely empty and the pressure switch is keeping the compressor off. If there's referigerant in the system from what you added you should be getting some pressure even with the car off now? I'd try adding another can, system holds 1.5 lbs.
The problem is the compressor isn't kicking on so it wont take the refridgerant. It went up to about 15psi but I still have a full can that it wont take.
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Old Jun 21, 2010 | 02:15 PM
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either jump the AC relay to get the compressor to cycle on, or use a tech2/hptuners/efilive to force the compressor on.

When I charged my system, I just used efilive and it was easy, but if you have 0 pressure, you need to find the leak, since it is more than just seepage to bring the system to 0. I would replace the drier as well as pull a vacuum before charging it.

Ryan
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Old Jun 21, 2010 | 02:21 PM
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Originally Posted by slow
either jump the AC relay to get the compressor to cycle on, or use a tech2/hptuners/efilive to force the compressor on.

When I charged my system, I just used efilive and it was easy, but if you have 0 pressure, you need to find the leak, since it is more than just seepage to bring the system to 0. I would replace the drier as well as pull a vacuum before charging it.

Ryan
I have about 15 psi. I don't think the gauge was seated fully when I first checked it. How do I jump the relay? I don't have access to the tuners.
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Old Jun 21, 2010 | 04:14 PM
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You don't need it. Run 2 jumper wires from the compressor direct to the battery. If it still doesn't come on, then at the very least the clutch is bad..and maybe the compressor too.
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Old Jun 21, 2010 | 04:24 PM
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+1

Did you pull a vacuum?


If you do it properly you should be able to push in enough 134a to have the compressor kick on.
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Old Jun 27, 2010 | 10:06 AM
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Originally Posted by fleetmgr
You don't need it. Run 2 jumper wires from the compressor direct to the battery. If it still doesn't come on, then at the very least the clutch is bad..and maybe the compressor too.
Im going through the same exact thing. What do you mean by 2 jumper wires? Where do you conect them on the compressor? The only thing I see coming off the compressor are the 2 very small wires that go to the plug.
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Old Jun 27, 2010 | 11:07 AM
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Pull that plug, and run one jumper from each of the 2 prongs you see, One to battery positive and one to battery negative. It helps a lot if your jumpers have alligator clips on them...you can get a set pre-equipped with alligator clips from Radio Shack. Make sure you don't have either the bare wires or the clips touching each other, or you'll see sparks.
Oh, and it doesn't matter which terminal goes to positive/negative.
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Old Jun 27, 2010 | 11:10 AM
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I talked to my mechanic at work the other day and he is going to vacuum the system and charge it up for me the right way... thanks for all the help guys.
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