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Thread: mc-2 wiring; No Yellow Wire at MC-2 Box

  1. #1
    blowe Guest

    Default mc-2 wiring; No Yellow Wire at MC-2 Box

    I am looking for a color chart for the wring on the MC-2 Wiring hardness.

    I have the MC-2 but do not have the cable assembly (PN 2411) and it is no longer available.

    On the MC-2, the 8 cable cluster (loom) on the end has the following colored wires in this order:

    P O Bl Bl
    G G Gr Wh

    P= Purple
    O= Orange
    Bl = Black
    B= Black
    G= Gray
    Gr = Green
    Wh = White

    On the wiring instructions, they all say that coil ‘A’ gets wired to Purple Black. Coil ‘B’ gets wired to Orange Yellow.

    The problem is I don’t have a Yellow wire in the 8 wire cluster at the end of the MC-2.

    Wondering which of the 2 Black wires corresponds to the yellow on the other side of the connector (the 2411 cable assembly).


  2. #2
    blowe Guest


    Does anyone even look at these forumns anymore???????

  3. #3
    otakar Guest


    I have the exact same problem. The colors coming from the box do not match the colors that are supposed to be in the pigtail. I have two blacks and three grays coming from the box and NO YELLOW. Please help

  4. #4
    otakar Guest


    Well I think that i got it figured out. I replaced the OE MSD plug because I did not have its mate, with a new 9 pole Molex 250V/11A connector and used 16AWG wires to supply the signals and 14AWG wires from the box to the coils. I made the cable 34" long, which I think is more than long enough. :thumbup: I had to change two colors because I could not find that color wire so my "gray" is now 14AWG red, which is the same color as on the bike, and my purple is now 14AWG blue. The rest of the colors are the same.

  5. #5


    The MC-2 is one of our older system and you are correct the harness is no longer available. From what I could still dig up on this unit is one of the black wire changes to yellow where the two connectors come together. The reasons for the change in wire colors were to show the defense between coil A and coil B. If you need anything please contact us at 1-915-858-3365

    Thank you


  6. #6
    otakar Guest


    OK here is the back of the OE MSD plug where I cut off the wires. The wire color arrangement is as follows in the picture.

    Green--White--Gray --Gray x2

    One of the Blacks must turn to yellow. It should not matter which one. The "Gray x2" position, the second wire is only a jumper to the previous gray pin. Why they did that I have no idea. Also why they elected to change one of the blacks to yellow I have no idea. Those two should be interchangeable.

  7. #7
    otakar Guest

    Default MC-1 MC-2 Wiring

    I seam to have these two systems figured out with the wiring. I have now bought a few more to experiment with. Since the wiring harnesses are no longer available I am making new ones for them. But I must also put a new plug on the unit itself. If any one wants one of these services let me know. I noticed that not all of them have the same wires coming out of the box, I have taken care of this problem with the new harnesses.

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