Help identifying A/C Compressor Clutch Coil

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hear

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I'm taking notes against the 97 FSM since I have 2 97's and neither have working A/C. One of the troubleshooting steps involves measuring current through & voltage across the "compressor clutch coil." The problem is the only place this seems to be mentioned is in this very section.

The referenced section 8w-40 details the A/C circuit operation, but does not mention the word "coil" anywhere. I would LOVE to know how to perform test (1) below.


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The coil is inside the pulley on the front of the A/C compressor. It’s essentially an electromagnet that engages the clutch (think of it like an electric slave cylinder). When they talk about connecting to the coil, it’s the clutch side of the electrical connector on the clutch. Those two wires are the two ends of the coil.
 
These are two pics of my 99TJ AC compressor. The wires you need to test are in the connector at the rear.
As mentioned you will not see a coil of wire, it's inside the front of the compressor.
You need a DC volt meter to test for 12volts to the wire plug I have tried to picture. Don't worry about an amp meter, at this time.
If have 12 vdc to the coil, with the engine running, and the center bolt isn't turning, that could be a COIL problem.
The switch that is tee into the high pressure line is not to considered, yet.
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So the clutch on my AC compressor went out. I know because it was making a high pitched squealing sound I couldn't hear...but it did pick up on video.

I spent hours with Sanden and a couple of their suppliers and dealers trying to find a replacement clutch...but... apparently I have a very early model compressor and nobody on the face of this earth makes a replacement clutch.

I ended up purchasing a new compressor... it's sitting on a shelf next to the hard top. Not in a hurry to install it...just installed a belt to bypass the compressor.

-Mac
 
sab said:
The coil is inside the pulley on the front of the A/C compressor. It’s essentially an electromagnet that engages the clutch (think of it like an electric slave cylinder). When they talk about connecting to the coil, it’s the clutch side of the electrical connector on the clutch. Those two wires are the two ends of the coil.
Click to expand...

I sure can't find that connector in the wiring section of the 97 FSM. I've looked at every connector multiple times now, and don't see any such thing.

I do now see that this connector was hidden around the far side, and also looks to be hard wired into the coil. From the passenger side of the jeep, none of this was visible, and I guess I didn’t look very hard.

Of course the a/c works fine so this is much ado about nothing.
 
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