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MM2 Headlight Problems Truck side

Discussion in 'Chevy Trucks' started by RipSaw, Nov 13, 2014.

  1. RipSaw

    RipSaw Junior Member
    Messages: 12

    HI this is my first post... I have a 2007 Chevy (classic)2500 HD Ext cab. I hitch up the isolation unit (4 port) and all wiring to my truck. the issue is that both low/high beams are on at the same time. The hi beam switch dose not make any changes when used. And I have removed both wiring harness and it function fine without them in. Plus change out the relay switch just to see, no change. I also unwrap both wiring harnesses to check for any damage and there was none. Any help would be greats... Thank you RipSaw
     
  2. Rick547

    Rick547 Senior Member
    from Indiana
    Messages: 535

    Do you have a wiring diagram for your plow? Better yet what kind of plow do you have?
     
  3. RipSaw

    RipSaw Junior Member
    Messages: 12

    My plow is a MM2 Hd Straight blade. And yes I have been working off the wiring diagram but I am not an expert at this either .
     
  4. What harness numbers are you using? You may get better results posting in the Fisher section but a lot of us monitor bothThumbs Up
     
  5. RipSaw

    RipSaw Junior Member
    Messages: 12

    I am not sure bought it used ... I think it was off a 2003 chevy and putting it on a classic 2007 Chevy 2500 HD .
     
  6. RipSaw

    RipSaw Junior Member
    Messages: 12

    And I fid repost this in fisher engineer section thank you
     
  7. Rick547

    Rick547 Senior Member
    from Indiana
    Messages: 535

    Okay, I found the electrical schematic. What pin connector do you have?
     
  8. RipSaw

    RipSaw Junior Member
    Messages: 12


    I have an eleven pin harness and a three pin on the other
     
  9. TMLGC

    TMLGC Senior Member
    Messages: 221

    I have a 2005 2500hd. I bought a used 8'mm2hd that came with wiring and a 4 port ISO. I brought it to the dealer to have all truck side stuff hooked up. They told me that I had to have a 3 port ISO and I could not use the 4 port that I provided.

    Unknown if that may be part of the problem the dealer I used is very good with a great reputation.
     
  10. chevyzrule810

    chevyzrule810 PlowSite.com Addict
    Messages: 1,238

    I have a 4 port green label isolation module on my 2006 and I've never had a problem
     
  11. buddymanzpop

    buddymanzpop Senior Member
    Messages: 599

    Post the part numbers off you headlight harnesses ports 3 and 4. What color label is on your isolation module?