Forum Discussion

John___Angela's avatar
John___Angela
Explorer
Feb 26, 2015

Location of ECM on an ISC350

Hi Folks. Some may recall I had a check engine light in the fall that I traced to a bad ground. While looking for this I had suggestions from some on also checking the ECU. The thing is I never actually found the ECM and I would like to know for future reference as I think the problem may still be intermittent. I wonder if someone could chime in on where it is and more specifically if you could give me a reference when looking straight down on the motor facing the back of the coach. It is a 2003 ISC-350 Caps motor.

Thanks in advance.

J and A
Class A

12 Replies

  • Ray_IN's avatar
    Ray_IN
    Explorer III
    Feb 28, 2015
    As you have noticed, it may be located most anywhere. Mine is above the engine, fastened to the access box,under the bed engine hatch. My MH is a 2000 Winnebago Ultimate Freedom DP, W/ ISC 8.3 350HP. The Allison TCM is right beside it.
  • Sully2's avatar
    Sully2
    Explorer
    Feb 26, 2015
    John & Angela wrote:
    larry cad wrote:
    On my Fleetwood American Coach, the ECM for my ISC is located in the same compartment as my battery bank right behind the rear wheels.


    Hi Larry and thanks for the input. We too have an ECM there but ours is the ECM for the Allison.

    Cheers.

    My tranny ECM was located all the way up front attached to the floor under the drivers seat
  • Sully2's avatar
    Sully2
    Explorer
    Feb 26, 2015
    larry cad wrote:
    On my Fleetwood American Coach, the ECM for my ISC is located in the same compartment as my battery bank right behind the rear wheels.


    Same with my ISC 330 engine
  • ScottG's avatar
    ScottG
    Nomad
    Feb 26, 2015
    Looked at my buddies 8.3 in his Kenworth and it is in the usual place on the side of the eng block.
  • John___Angela's avatar
    John___Angela
    Explorer
    Feb 26, 2015
    larry cad wrote:
    On my Fleetwood American Coach, the ECM for my ISC is located in the same compartment as my battery bank right behind the rear wheels.


    Hi Larry and thanks for the input. We too have an ECM there but ours is the ECM for the Allison.

    Cheers.
  • larry_cad's avatar
    larry_cad
    Explorer II
    Feb 26, 2015
    On my Fleetwood American Coach, the ECM for my ISC is located in the same compartment as my battery bank right behind the rear wheels.
  • Tom_Barb's avatar
    Tom_Barb
    Explorer
    Feb 26, 2015
    Ivylog wrote:
    ScottG wrote:
    It is attached to the drivers side of the engine block

    Scott is correct since he is talking about a PU


    Post #1, asked about an "ISC 350" it would be quite some pick up that would carry a Cummins 8.3 ISC. That is the engine we have, and I have had the same symptoms and fixed it by removing the ECM and cleaning the back mounting points and replacing it.
  • Ivylog's avatar
    Ivylog
    Explorer III
    Feb 26, 2015
    ScottG wrote:
    It is attached to the drivers side of the engine block

    Scott is correct since he is talking about a PU
  • John___Angela's avatar
    John___Angela
    Explorer
    Feb 26, 2015
    Thanks for the answers so far all. I will be in there tomorrow lubing the exhaust brake so Ill check it out then.

    J and A

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