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Discussion in 'Fisher Engineering Discussion' started by ed39, Oct 11, 2009.

  1. ed39

    ed39 Senior Member
    Messages: 120

    i know this has been asked 100s of times but i cant find what im looking for. I want to convert a mm2 3 plug to work with my 2 plug setup, i cant seem to find an exact procedure on how to do this. ive seen it asked but no clear answer. Whare can i find wiring diagrams of the 2 systems so i can see how they match up. my system is a 9 pin with the 2 relays
  2. cubicinches

    cubicinches PlowSite.com Addict
    Messages: 1,412

    Better off to convert the truck to three plug. Three plug uses the isolation module with weather pack connections... no relays. If you want to convert the plow without hacking up harnesses, you need new headlights. Probably less money to convert the truck, and you wind up with a better setup in the end. Just my opinion.
  3. Crash935

    Crash935 2000 Club Member
    Messages: 2,377

    Its cheaper to switch the plow side harness than the truck side.

    Harness # 61438. (9 pin)

    Only have to change the harness on the plow to the headlights and valves.
  4. RepoMan207

    RepoMan207 PlowSite Fanatic
    from Maine
    Messages: 5,031

    Crash is definitely right on this. I just swapped the truck over to the 3 Port ISO. If the 9 pin harness off my plow wasn't already spoken for I would sell it to you.
  5. fordpsd

    fordpsd Senior Member
    Messages: 308

    When i bought a mm2 last year i converted the plow side to the two plug. Seemed to be the cheapest and the easiest way.