ABS light link with brown, tail and running lights, wire.

Discussion in 'Volvo Forum' started by BL3FoodLionMech, Nov 22, 2020.

  1. BL3FoodLionMech

    BL3FoodLionMech Bobtail Member

    Joined:
    Nov 22, 2020
    Messages:
    3
    Thanks Received:
    0
    0
    Good afternoon everyone,

    I am here to seek some help. I work at Food Lion distribution as a mechanic. I'm not very good and I work only on trailers, but my superiors have also looked into this trailer and it has them scratching, or, "Scratching my head with one hand and my but with the other", as my lead had said.

    The ABS light comes on when plugging pigtail in and stays on. Now here is the part that we am looking into and trying to figure out. I went into the nose box, they did as well, but what I was looking for was the wire that turns off the ABS light. See what they did was put power to the auxiliary, which, cycles through the ABS but the light does not come on at all. Now the brown cable, I learned when disconnecting it, turns off what it runs, Tail and Running Lights, but also the ABS light.

    So the ABS is tied into the brown wire and I don't know how to fix it. The trailer is a 20 series utility trailer.

    Much appreciated,
    Leon
     
  2. 6cuda6

    6cuda6 Light Load Member

    Joined:
    Oct 9, 2020
    Messages:
    259
    Thanks Received:
    176
    0
    Do you get an ABS code? The light on indicates you have an ABS fault.....
     
  3. BL3FoodLionMech

    BL3FoodLionMech Bobtail Member

    Joined:
    Nov 22, 2020
    Messages:
    3
    Thanks Received:
    0
    0
    No fault code. The ABS is cool, not the light though. It is weird and like working on ABS problems but this one is way cray.
     
  4. nasriza

    nasriza Road Train Member

    Joined:
    Feb 1, 2013
    Messages:
    2,398
    Thanks Received:
    2,074
    Location:
    Chicago, IL
    0
    The brown wire is what gives the trailer module signal to say brakes are being applied memory serves me correctly that should go to the brake light wire connected all the way in the ack usually input for abs module to tell it that the service brake is being applied.
     
  5. BL3FoodLionMech

    BL3FoodLionMech Bobtail Member

    Joined:
    Nov 22, 2020
    Messages:
    3
    Thanks Received:
    0
    0
    So when I unplugged the brown wire all of the lower lights go out, turn signal brake lights and now ABS light, but of course the upper lights turns signal and brake lights still work. The ABS stays off.
     
  6. SmallPackage

    SmallPackage Road Train Member

    Joined:
    Dec 20, 2019
    Messages:
    5,666
    Thanks Received:
    18,108
    Location:
    Marion Texas
    0
    Blue wire is for abs in the nose plug. Abs light should be independent of the taillight and marker light circuit. Brown is tail lights and black is marker/icc lights.
     
  7. devedo

    devedo Light Load Member

    Joined:
    Aug 11, 2015
    Messages:
    114
    Thanks Received:
    43
    0
    The abs light should be on it's own circuit running to the abs module and no other lights.

    Brown/black are for tail, marker, and clearance lights.

    Depending on which abs manufacturer the trailer has...you can look up wiring diagrams online and it's a pretty easy fix.

    I would look around by the abs light for a harness that had been cut because it sounds like someone didn't know that was an abs light and thought it was a marker light not working and "fixed" it.