A/C Compressor Clutch not engaging?

Good Afternoon All,
I have one that seems to be puzzling me right now. I have a 1999 Cherokee Sport with the 4.0L engine, and today I have discovered that I may have some trouble with my A/C. Today has been the hottest day so far this year in Northeast Tennessee, and I was out doing some work on the Jeep today and noticed when I turned my climate control knob over to max/ac that the air coming out of the vents was none too cool. Upon further investigation, I determined that the electric cooling fan for the radiator was cycling like normal when I turned on the A/C, but watching the front of the compressor, the clutch for the compressor did not seem to be engaging. I tried cycling the system on and off a couple of times, but nothing changed. I decided that there could possibly be a blown fuse or relay, but upon switch the 20amp fuse for the a/c clutch with another and switching the relay with my fog lamp relay, that neither was blown. I am wondering does anyone know if these Jeeps will not cycle the compressor clutch if the refrigerant is low? Or does anyone know anything that I should check in order to determine what could be wrong? Any suggestions are greatly appreciated!

I have the same problem with my 98, only the compressor clutch will work sometimes. If its low on refrigerant, the compressor clutch will not engage to protect the compressor; however the AC systems in our XJ's are not known to be very hearty. When this happened to mine, I bought a can of R-134a with a gauge and attempted to check the level. I ended up adding some refrigerent which did not solve the problem. Next, I tried replacing the low pressure switch as they are often the culprit. I should have tested my way to a solution instead of buying the part, but at least I have an extra switch now if that ever fails. I'm now leaning towards the clutch pack in the compressor needing replacement, but when I looked around last summer I could only find the entire compressor for sale. I've read that you can remove the old clutch, and simply replace it with a new (used) one from a junkyard and I'll probably try that this summer. When my clutch engages the system works beautifully and blows cold air. You might see if it will take freon and kick in....if that's the case, you may have a leak to chase down. Some of the kits are sold with a dye to help you locate the leak....I believe with a UV light or something like that. Others with more experience will probably chime in.

I think I may be having the same problem that you are, because just a little while ago, I went out started it up, turned the a/c on, and watched the clutch. It did engage, but was very slow a first and then it starte spinning faster. I went inside the car and the air was cold, however if you rev the engine the slightest bit while the clutch is engaged, it sounded as if I had birds in under my hood. The noise sounds as if it is coming from the opposite side of the engine as the a/c compressor. I think that the clutch may be stressing the belt causing the belt squeel? Any more advice is appreciated!

I'm having the same problem with my 2000 XJ. My AC worked great last year but the first time i went to use it this year it didnt work, my clutch is not engaging. I'm going to try to find a clutch for it...anyone get their problems solved?

With the vehicle running& the A/C on high. The single wire connector that goes to the A/C clutch, Open it up & check the side that comes from the harness (Engine side),There should be 12V there, If not the clutch is most likely OK & you probably need your A/C serviced.

Now With the engine off, Using a jumper from the + side of the battery, Touch the Hot wire to the stab on the compressor side of the open connector, You should see the clutch pull in, If this happens clutch is most likely OK & you probably need your A/C serviced.

Good Luck.