PCM part number question.

Discussion in 'KJ General Discussion' started by Boomhawr, Jul 10, 2019.

  1. Boomhawr

    Boomhawr Full Access Member

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    So I had to order a new PCM for my 06 Liberty. It came in but the last digit of the number is wrong. Mine was a 939AD and the one they sent was a 939AC. When I called they said it’s just a software update. I just wanted to make sure this is correct and not going to be a problem.

    Thank you for any help.
     
  2. Billwill

    Billwill Full Access Member

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    Yes the last two characters are revision numbers and are all interchangeable but ideally you want to have the higher digits ie. AD and not AC as the AD has the newer software!

    Probably no way of knowing what software improvement came with the AD unit...probably a minor issue.
     
  3. LibertyTC

    LibertyTC Well-Known Member Staff Member Moderator

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    By the sounds of it, a dealer visit may be required to upgrade to the latest firmware.
     
  4. Boomhawr

    Boomhawr Full Access Member

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    Thank y’all for the help. I installed it, and I’m having the same problems I was having with the old unit. Don’t know if they sent a bad PCM or if the shop misdiagnosed what the issue was. ☹️ Guess I’ll be going to the dealership then
     
  5. Robert O

    Robert O New Member

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    Why did you have to replace the ecm
     
  6. Billwill

    Billwill Full Access Member

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    Yeah why did you have to replace the PCM/ECM?
    Could be something else wrongsuch as a wiring problem.

    Is yours a Gasser or a CRD....gasser use PCM and CRD uses an ECM...not serious what you call it. The 06 gasser I think has the TCM and PCM in the same module...not separate.

    VIN and SKIM code have to be entered into the new module.

    Too lazy to look up the part number I am afraid as the Parts Fiche is a pain to use!:confused: