MCCUTCHEON4

I have a 2001 Cherokee, the the AC pump constantly cycles on and off when the AC is not in use. Why does it do this?

I drove a 98 for almost 9 years that did the same annoying thing.

I searched on the topic but didn't find anything.

Thanks

ehall

Defrost setting cycles the compressor. AC acts like a dehumidifier of sorts, basically the evaporator core in the dashboard will draw moisture from the surrounding air, which helps evac moisture off the windshield

djb383

The vent selector has 7 positions....5 of those 7 positions engage the compressor. The 5 vent positions circled in yellow below engage the compressor, the 2 positions not circled do not engage the compressor. Most all vehicles with a dial type HVAC vent selector are like this. Very functional, not complicated at all. No need to use the 2 positions furthest to the right unless the windshield fogs up on the inside or ices up on the outside. Inside is called defog and outside is called defrost. The defrost position will also require turning the temp selector **** to the heat (red) position.

Rapid compressor cycling can also mean the system is low on refrigerant.

MCCUTCHEON4

That make sense.
Thanks.

My AC is not working.
I don't plan to have it serviced until summer, If I pull the power connection to the AC clutch I won't cause damage to a relay or something else will I?

Thanks again,
Gregg

MCCUTCHEON4

Got it. The AC isn't working, it may be low on refrigerant as you said.
The clutch on the AC pump makes bunch of racket when cycling so
I want to disconnect it for now.

I just bought an 01 to replace my used up 98 and have repairs that are a priority to the AC.

Thanks,
Gregg

MCCUTCHEON4

What is the small switch in the red circle for?

ehall

You'll be fine disabling the compressor

GreenClassic

If the clutch is making a bunch of noise, it could be the reason your AC isn't working. Mine would stop working intermittently, and it was the clutch was worn out. I got a rebuild kit for the clutch and it's been good ever since.

Radi

That's where the factory fog light switch should go.

Like Ehall said, no problem disconnecting the plug on the compressor. A lot of them are probably running around that way.

CCKen

Someone installed an AC bypass switch. It opens the control wire from the Low Pressure Compressor Cycling Switch on top of the Accumulator. It essentially does the same thing as removing the connector from the Low Pressure switch. In this mode you can use any selection on the Mode Selector without engaging the AC.

MCCUTCHEON4

Good idea.


I remember older pursuit vehicles having an "AC cut out"




Gregg

CCKen

Gregg,

Do a good deed and go to your User CP and fill out your Jeep data. Year, Engine, Transmission, etc.

metaldemon7

My 98 XJ did that till I put R134 in it. The system was 16 years old, and never recharged. One bottle, and all is good. On my 94 XJ, that I just got. The whole system is coming out. The AC delete bracket should be here on Monday at Advanced Auto. $42 for something I really don't use. My son uses the AC on the 98 XJ

1arunem

Low freon level will make it cycle (low pressure).

djb383

Negative on the a/c bypass and fog light switch. Our XJ is a plain Jane stripped down SE model.....no power anything. The previous owner installed power door lock servos in the doors and liftgate and that switch locks/unlocks the doors/liftgate.