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relay question

Discussion in 'Western Plows Discussion' started by Boomer123, Nov 27, 2015.

  1. Boomer123

    Boomer123 Senior Member
    Messages: 371

    I have an older relay system before the isolation modules came out. My question is do the relays only affect headlights and turn signals. Do they have anything to do with the up down left right operation of the Plow.
  2. Western1

    Western1 Senior Member
    from MI.
    Messages: 752

    Only the headlights. They don't affect up down left or right.
  3. dieselss

    dieselss PlowSite Fanatic
    Messages: 11,390

    Yep only headlights, no turn signals.
  4. mishnick

    mishnick 2000 Club Member
    Messages: 2,353

    All true, in fact, for testing purposes you can install a new control harness to the handheld / joystick controller, power relay (solenoid) and plow for testing without connecting any relays. On some old ratty systems I have just cut an terminated (insulated with heat shrink) the wires going to the relays and then installed my own headlight switch directing power from truck to either OEM lights or plow lights.

    If you are having trouble with functions you need to look at the three wires (if it's a straight blade) that feed the coils from the controller. There is a wire for each function. Of course also check the individual valves, coils and common ground wires to the coils.

    If you have function troubles give us details and we will help you narrow it down but we need to know the model of plow (straight blade or V), how many plugs it has at the grill and if it's an old two plug, how many pins in the plug with the small contacts, 7. 9 or 12 pins.

    For now perhaps this link to the electrical schematics will help http://library.westernplows.com/ddcommon/dd_pdf/pdfs/22373.07_110108_for_web.pdf
    Just identify your system and look for the schematic, they are all in this manual.....
  5. Boomer123

    Boomer123 Senior Member
    Messages: 371

    I think I have 6 relays taped together. That seems like a lot just to control head lights.
  6. mishnick

    mishnick 2000 Club Member
    Messages: 2,353

    There are six relays in some cases. You probably have quad headlights and a DRL system (daytime running lights). Does seem like a lot but every one of them is needed for proper functionality.
  7. 1CoolZ71

    1CoolZ71 Junior Member
    Messages: 2

    I bought a 2001 GMC but took the wiring from my 1992 Chevy.
    I have installed everything and the plow works fine but of course the lights don't.

    After researching, I see I need wire module 26071 and more relays.

    My question is: Do I really need to use the relays for the DRL's and the parking lamps or can I get the harness and use 4 relays for only the headlights?
  8. Philbilly2

    Philbilly2 PlowSite Veteran
    Messages: 3,767

    Depends on what all you want to work properly or not.
    Last edited: Nov 30, 2015
  9. 1CoolZ71

    1CoolZ71 Junior Member
    Messages: 2

    My DRL's are burned out anyway and the parking lights work already by direct wiring them
  10. mishnick

    mishnick 2000 Club Member
    Messages: 2,353

    The problem is figuring out how to make everything else work when you start removing parts.... Kinda like the first surgeons learning that you could take out a person's appendix but you couldn't remove their heart and expect them to live.

    Perhaps if you just looked up the schematic for your truck without the DRLs and go with that. There are several different types of headlight harnesses labeled alphabetically (E, F, G etc) but from what I see the DRL and non-DRL systems use the same harnesses. I can't tell you which diagram to use because I don't know if you have a straight blade or MVP, or if you have 7, 9 or 12 pin control harness. (That would be the number of pins at your grill on the plug with the small pins) But if you have some electrical aptitude and skill perhaps you can identify your plow and then find the correct page on this electrical manual....