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a/c compresor running all the time

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Old Mar 12, 2011 | 11:49 PM
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Default a/c compresor running all the time

i think my pump is running constantly. one of the reasons is im getting roughly 11.2 mpg on last tank, my ac fan runs pretty well of start up and the pressure line on the ac is frozen all the time.

anyone have thoughts on this? maybe its not? if it is possible fixes? any help would be greatly appreciated.
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Old Mar 13, 2011 | 09:02 AM
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This thread should point you at the right part, it's opposite of what I had happen, and the same thing the new one is doing now lol....it's on top of the black condenser canister with a plug on top
https://www.cherokeeforum.com/f2/c-issues-56728/

Edit- forgot to mention you can also just Unplug it until you get a new One if you're not using the ac.

Last edited by storm101; Mar 13, 2011 at 10:49 AM.
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Old Mar 13, 2011 | 11:33 AM
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Where is your selector switch set? Any of the 5 positions circled in yellow will engage the compressor.
Attached Thumbnails a/c compresor running all the time-002-copy.jpg  
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Old Mar 13, 2011 | 12:06 PM
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20% on defrost and 80 on defrost and feet.
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Old Mar 13, 2011 | 12:18 PM
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That's why your compressor runs 100% of the time.
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Old Mar 13, 2011 | 10:43 PM
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Originally Posted by djb383
That's why your compressor runs 100% of the time.
I beg to differ on this, Even on the heat the compressor should cycle on and off....the lines shouldn't freeze up with visible "frost".

There was even a service bulletin out at one point due to the lines freezing up, the fix was a new cycle switch (it was definatly an older one) I wish I still had access to ondemand to look that up again....

Bottom line, yes the ac pump should engage on the two defrost settings, but should cycle on and off, if not there's and issue, and my bet says it's the cycle switch....again if those lines are visibly froze, there's a problem.
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Old Mar 14, 2011 | 09:26 AM
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Yes, the compressor will cycle on/off in any of those 5 selector positions. IF the system has the proper amount of refrigerant, the compressor will be engaged, +/- 99% of the time and disengaged +/- 1% of the time. If refrigerant is low, the compressor is on less.

My point was, the OP probably didn't realize that the 2 defrost positions engaged the compressor. Since he used one or the other of the defrost positions 100% of the time, the compressor is engaged +/- 99% of the time. It will cycle off momentarily, a few seconds at a time.

If the windshield DOES NOT need to be de-iced/de-frosted/de-fogged....don't select either of those positions because if u do, the compressor runs. Only 2 of the selector positions do not engage the compressor.
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Old Mar 14, 2011 | 11:00 AM
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Even with the compressor running, you shouldn't be getting 11.8 mpg. The compressor only takes app. 1-2 mpg, unless you have a lift and locker, etc.
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Old Mar 14, 2011 | 12:41 PM
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Why would a locker effect mpg?
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Old Mar 14, 2011 | 12:45 PM
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Originally Posted by djb383
Why would a locker effect mpg?
I shoulda rethought that one. I was thinking of lifted parts and offroad components and didn't think to correct myself. No, a locker would not effect mpg's. Bigger tires and lifts would.
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Old Mar 14, 2011 | 12:50 PM
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Gotcha.......
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