2001 Grand Cherokee AC PCM problems

nc_ntimid8rnc_ntimid8r Member Posts: 1
edited September 2010 in Jeep
I have a 2001 Jeep Grand Cherokee 4.0L and my AC quit working. I thought it was the compressor clutch plate so I fixed the spacer on it and still nothing. Started checking continuity through AC Clutch relay in fuse box and found out I was not getting a signal from the side connected to the PCM to tell it to come on. Got a wiring diagram and found out there is a PCM Clutch relay control. I do not know what the PCM checks for before kicking the relay on. I have jumpered the relay and the compressor kicks on and AC works. If it helps, I replaced the water pump and t-stat about 2 weeks prior to this happening. Also, I have noticed that as soon as you turn on the switch for the AC (compressor still doesnt run but the car acts like it is on), the aux. fan kicks on, even if the car temp is below 110. Usually it doesn't kick on until the car gets to 210. Any help?

Here's the kicker, hooked it up to an OBD tool and no codes came back...Think I have Gremlins in this thing!


  • tidestertidester Member Posts: 10,059
    You may want to have a look at Jeep Grand Cherokee PCM and Jeep Grand Cherokee PCM Module Replacement.

    tidester, host
    SUVs and Smart Shopper
  • mandm4mandm4 Member Posts: 7
    I am having the same promlem. Just got done replaceing the head gaskets on my 2000 JGC 4.7. everything went fine. after all was done my ac compressor is not coming on. check all conectors. disconnect the ac switch and jump it compressor came on. replaced the ac compressor switch. still not working. did not disconect any of the ac system when doing the heads. plus check all fuses in the engine comparment. good. is there something else that i am missing, besides replacing the computer, because i think that would be the next thing. any help would be cool thank you
  • mortiismortiis Member Posts: 1
    Hello out there. I have a 2001 grand cherokee 4x4. I want to install a radio with satellite radio option in it rather than install the separate after market unit. Anyone know if later model radios will fit my 2001? Thanks, Bill
  • erm1974erm1974 Member Posts: 3
    For any radio fitting in your jeep just go to http://www.crutchfield.com they have all the specs for any car truck ect and every radio and option and free wire harness if you buy the radio from them..hope this helps.
  • champ424champ424 Member Posts: 4
    I recently had some of the same problems and then some. Car would stall out after 3-5 seconds... Instrument cluster was illuminated but the gauges didnt work. Security light was on... Paid 125 to run diagnostics. Came back PCM error. They wanted to charge over 1000 for new PCM and labor. Found remanufactured PCM online for 200. Took 30 minutes top to change. Easy job anyone can do and save money. Their website is www.ALLCOMPUTERRESOURCES.com.. highly recommended for PCMs
Sign In or Register to comment.