AC cutch lead

VegasAnthony · May 2, 2005

I found a wire comin from the clutch (im trouble shooting the system)
cept it only has one lead going from the plug which is spliced into two wires

OK now one goes to the clutch ity looks like
and the other looks grounded to a plate on the clutch
does this make sense Im I missing somethin

should nt the lead coming from the wire harness to the compressor
register a 12 volt reading when the AC is turned on

WobblesXJ · May 2, 2005

there is only one lead going in then it comes out and grounds completing the circuit.

If you have refridgerant in the system then yes you should have 12v there with it turned on, but if you're out there's a switch that won't let voltage pass preventing the clutch from engaging. (this is to prevent your compressor from burning up with no oil in it, the refridgerant also contains a lubricant)

If you want to see if the clutch will engage, make sure the engine is off and touch the incoming lead to the positive post on your battery, you should hear it click.

NotMatt · May 2, 2005

Indeed, if you take that little "package" of wiring apart, you'll find that only one of the wires is actually hooked up to voltage... the one that screws into the top of the compressor is NOT. Test by unplugging the connector from the pressure sensor and touching it to the positive battery terminal. If it's working, the clutch should engage and the compressor will spin. If that's the case, and the compressor itself doesn't engage with the A/C on, then you either have a bad pressure switch or your system has no refrigerant in it (thus the pressure switch is keeping the clutch off to prevent burning up the compressor with no lubrication.

pair8hd · Jun 28, 2005

NotMatt said:
Indeed, if you take that little "package" of wiring apart, you'll find that only one of the wires is actually hooked up to voltage... the one that screws into the top of the compressor is NOT. Test by unplugging the connector from the pressure sensor and touching it to the positive battery terminal. If it's working, the clutch should engage and the compressor will spin. If that's the case, and the compressor itself doesn't engage with the A/C on, then you either have a bad pressure switch or your system has no refrigerant in it (thus the pressure switch is keeping the clutch off to prevent burning up the compressor with no lubrication.

Where is the pressure switch?
How do i reset it so I can recharge the system?

My compressor will not engage.
'90 Xj that has been convert to R-134a.

TIA

WobblesXJ · Jun 28, 2005

If your system is low you're going to have to empty it and pull a vacuum on it before you can put more in.

Possibly something to let professionals do if you aren't that familiar and don't have the equiptment.

old_man · Jun 28, 2005

Since when do you have to evacuate a system that is low on refrigerant? I've done tons of vehicles over the last few decades and as long as the system hasn't been cracked open, charging is fine. Evacuation is only needed if the system has gotten air or other impurities in it.

If the system is too low to get the compressor running, slowly add freon and short across the low pressure switch to get the compressor running. The low pressure switch is to keep from burning up the compressor if it runs out of freon. Running it for a short period of time won't hurt it.

WobblesXJ · Jun 28, 2005

Just speaking from my experience. I'm by no means an expert. When mine got low I couldn't fill it without pulling a vacuum first. I would assume if refridgerant came out a leak something took it's place via that same leak.

AC cutch lead

VegasAnthony

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WobblesXJ

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NotMatt

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pair8hd

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WobblesXJ

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old_man

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WobblesXJ

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