A/C Help

[silver_xj]

Today after replacing my starter I began to trouble shoot my A/C system that is blowing hot air. All components are there and the compressor seems to have been replaced as its cleaner than the other accessories. The first think I did was try to fill the r134a with quick fill setup from the parts store. When I hooked it up, the pressure gauge pegged out until I would squeeze the trigger to input more refrigerant into the system. So I relieved the extra system pressure and followed the instructions on the can to fill to the correct pressure. The XJ is still blowing hot air and I noticed that compressor clutch wasn't kicking on. I've checked the relay and fuse under the hood and they are both fine. I know the clutch wont engage unless there is enough pressure in the system so I decided to test the gauge on the recharge kit on another vehicle before the can was empty. It checked out fine. Am I looking at buying another compressor or is there something else I can test/check. FWIW my coolant temp sensor and electric fan work as the gauge in the dash reads 210 (at operating temp) and the fan will kick on around 217ish degrees.

[4.3LXJ]

If you have it charged, then the first thing to check is the low temp pressure switch. It is a safety switch that will not let the compressor engage. It will be located on the high pressure line. Not sure exactly where on the 2000, but you can bypass it by unplugging it and bending a paper clip and inserting both ends into the plug. The compressor should come on then

[silver_xj]

I'll look for it tomorrow. I think I know where its at as I reseated the connections for the compressor today. So just to clarify, I unplug the vehicle harness connector and jumper the compressor connector to it's self?

[nickxj94]

Check the fuses in the pass side kick panel first my 00 did that when the o2 sensor shorted out and kept popping the fuse. The switch 4.3 is talking about is on the pass side by the Hood hinge and firewall.

[silver_xj]

My pass side kick panel fuses are not labled. I did however find a pic that showed a blue 15 fuse on the firewall side about 4-5 up. I checked this and it was good

[silver_xj]

*side note* what fuses do I check for the o2's? I want to check mine to make sure I'm getting maximum MPG's

[nickxj94]

Right here is the switch he is talking about. 2514

[nickxj94]

Check the fuses in the pass side kick panel first my 00 did that when the o2 sensor shorted out and kept popping the fuse. The switch 4.3 is talking about is on the pass side by the Hood hinge and firewall.

Fuse 10 should be the one to look at on the 2000 it controls the AC clutch relay. 15 amp mini fuse

[nickxj94]

*side note* what fuses do I check for the o2's? I want to check mine to make sure I'm getting maximum MPG's

Fuse 10 controls the o2 sensors as well and a few other things.

[nickxj94]

I found the right fuse diagram on Cherokee forum don't bother looking at 99 and older cause there different the 00-01 changed up a little on there wiring and fuse boxes. It took me a few hours of diggin on the interweb to find the right diagram.

[4.3LXJ]

I'll look for it tomorrow. I think I know where its at as I reseated the connections for the compressor today. So just to clarify, I unplug the vehicle harness connector and jumper the compressor connector to it's self?

Yes

[silver_xj]

Right here is the switch he is talking about. 2514


The one on the left or the black one on the right near the green cap?

[nickxj94]

The one on top of the evap the light is pointed at

[silver_xj]

Thanks for the clarification. I'll go jumper it with a paperclip or speaker wire and see if the clutch kicks in.

[silver_xj]

Well I pulled the connector off and jumped the two prongs with a paper clip and nothing happened. I do believe that I heard a faint click. Does that mean my compressor is bad? If so what is a good replacement unit?

[nickxj94]

Well I pulled the connector off and jumped the two prongs with a paper clip and nothing happened. I do believe that I heard a faint click. Does that mean my compressor is bad? If so what is a good replacement unit?

I would try to get what come on them, rock auto should carry them

[silver_xj]

I'll be window shopping at advance, autzone, pepboys, o'reilys and rock auto until payday. Its getting a little to warm to not have A/C..

[nickxj94]

I'll be window shopping at advance, autzone, pepboys, o'reilys and rock auto until payday. Its getting a little to warm to not have A/C..

Yeah I kicked mine on the other day in my 94 I usually never run it unless I start sweating driving lol

[4.3LXJ]

Well I pulled the connector off and jumped the two prongs with a paper clip and nothing happened. I do believe that I heard a faint click. Does that mean my compressor is bad? If so what is a good replacement unit?

I assume the engine was running when you did this. Verify power to the clutch with a test light or meter before you buy a compressor

[silver_xj]

I assume the engine was running when you did this. Verify power to the clutch with a test light or meter before you buy a compressor

Yes the engine was on. How many volts should the clutch get when I hook up my volt meter to it?

[4.3LXJ]

12 V

[silver_xj]

ill toss the meter on it when I get home. im not holding my breath though.

[silver_xj]

Ended up working on the driver door speaker connection.. I try the volt meter tomorrow

[silver_xj]

Tested the volts at the compressor (the screw in the right side where 3 leads are) and got - .04 volts DC. The engine and A/C were both running. Any thoughts?

[4.3LXJ]

You should be getting more than that. Jump it and see what happens

[silver_xj]

do I disconnect the lead from the harness and just run a lead from the positive terminal?

[4.3LXJ]

There should be a plug on the lead to the compressor. You want to jump from the positive source to that wire. Even not running, you should see the clutch go in. If not, clutch is probably toast. You can also ohm it from that wire to ground. If open, it is toast.

[msmoorenburg]

Well I pulled the connector off and jumped the two prongs with a paper clip and nothing happened. I do believe that I heard a faint click. Does that mean my compressor is bad? If so what is a good replacement unit?

when you have the plug jumped verify you have 12volts at the compressor before replacing the a/c compressor or clutch

[silver_xj]

I may have done this wrong as I jumped the two "male" prongs on the accumulator. Should I have jumped the female ports of the harness??

[4.3LXJ]

Yes, female connections in the harness

[silver_xj]

Yes, female connections in the harness

Tried this with a paperclip and nothing happened.

[4.3LXJ]

Getting current to the compressor?

[silver_xj]

I forgot to check current when I had my jumper paper clip in. I got discouraged because the clutch didn't come on.

[Mudderoy]

I forgot to check current when I had my jumper paper clip in. I got discouraged because the clutch didn't come on.

Current is hard, voltage is easy. Check to see if you are getting 12 volts to the compressor.

[silver_xj]

Sorry. I meant Volts. I donated blood that day and had a beer or two a few hours after. I wasn't really all there mentally. LOL I'm going to take it for a free A/C check tomorrow and see what they say. Driving with out A/C this week has made fixing this a top priority.

[silver_xj]

well I took the xj in for a free ac check this morning. A few hours later they called and sais the compressor wasnt getting power and it cost $50 to diagnose it. about an hour after that they called again and said a fuse was bad. I know I checked the ones under the hood and in the cab... At that point I was qupted $250 total out the door to get it fixed. im still waiting on a call back. I hope something else didnt break.

[nickxj94]

well I took the xj in for a free ac check this morning. A few hours later they called and sais the compressor wasnt getting power and it cost $50 to diagnose it. about an hour after that they called again and said a fuse was bad. I know I checked the ones under the hood and in the cab... At that point I was qupted $250 total out the door to get it fixed. im still waiting on a call back. I hope something else didnt break.

Was it that #10 fuse?

[silver_xj]

it was a 20 amp fuse under the hood, one of the yellow ones. I know I checked it.

[silver_xj]

Well after spending money at the shop I am disappointed. I had, what I thought was belt squeal, but apparently it was the compressor clutch. I managed to break the belt before I realized it was the compressor clutch causing drag... Looks like I'm going to be buying a new compressor after all. For now I'm out 34 bucks for a new belt, 250 for A/C service and I still get the pleasure of riding in the Texas heat... #XJlife?

[4.3LXJ]

Wait a minute here. If a compressor breaks a belt, it is seized. So, you pay out to have your AC fixed and the compressor doesn't work. As they say, something smells rotten in Denmark. Did it ever work for you after they fixed it?

[silver_xj]

yes it was working but would squeal on ocassion. I tried to snug up the belt but it broke so I put a new one on. I guess the compressor is partially seized as it only happens when I turn on the A/C

[4.3LXJ]

That is when they seize. The rest of the time they act as and idler pulley

[Mudderoy]

Sorry. I meant Volts. I donated blood that day and had a beer or two a few hours after. I wasn't really all there mentally. LOL I'm going to take it for a free A/C check tomorrow and see what they say. Driving with out A/C this week has made fixing this a top priority.

Hell I probably say current some times myself, no issue, one is just a lot easier to check.

[silver_xj]

That is when they seize. The rest of the time they act as and idler pulley

Yeah. That's what I figured. I just can't believe that it worked fine for a day and then gave out. :bang: I'll be on the hunt for a decently priced replacement with in the next few weeks.