Silverado trailer brake light problem

Discussion in 'Trucks and Trailers' started by robertsturf, Dec 19, 2006.

  1. robertsturf

    robertsturf LawnSite Bronze Member
    Messages: 1,406

    Ok here goes. I own a 2003 Silverado 2500HD with the towing package. I am having a trailer brake light problem with the right brake light. I have tested at the plug and fuse box and have no power. Other than replacing the harness is there anything else I should check? The fuse box under the hood doesn't list any fuses for the trailer brake lights. The fuse box by the drivers door has the fuses for the trailer brake lights and I have tested for power there. Left brake light on trailer works fine. Thanks for your input.
  2. mojob

    mojob LawnSite Senior Member
    Messages: 515

    Is there a connection at the back of the truck where the trailer plug harness plugs into the truck's harness? I would think think they would tie it in there not up at the fuse panel.
  3. robertsturf

    robertsturf LawnSite Bronze Member
    Messages: 1,406

    There is a 7 way plug at the rear bumper of the truck and no power at that terminal.
  4. mojob

    mojob LawnSite Senior Member
    Messages: 515

    I'm talking about a connection under the bed that connects the plug to the trucks main harness. I think that's how they hook it up. Follow the wires from the plug toward the front of the truck.
  5. Total.Lawn.Care

    Total.Lawn.Care LawnSite Senior Member
    Messages: 840

    Dismount your 7-Way plug and test the bare wires for the power. Sometimes the connections in the plugs either corrode, or become weakened and disconnected and if you test the bare wires and have power, you can just replace the plug by making good connections with new freshly stripped wire and be okay.
  6. Canon Landscaping

    Canon Landscaping LawnSite Senior Member
    Messages: 259

    there is a fuse under the hood i have an 02 hd and had the same problem there is a fuse inside the cab and under the hood.
  7. robertsturf

    robertsturf LawnSite Bronze Member
    Messages: 1,406

    I cannot find a marking in the fuse box under the hood for the trailer brake light. The fuse under the dash is good and I am not getting power to that! The 7-way plug in the back would not have power to it if I don't have power at the fuse box. Where would I find the fuse in the box under the hood?? I have looked for the marking several times and no luck.
  8. mojob

    mojob LawnSite Senior Member
    Messages: 515

    If the right brake light worked at one time and now it doesn't and you suspect the fuse under the hood, then just start checking fuses to see if they're blown. If you have 12v on one side of the fuse and zero on the If there's no voltage on either side of the fuse, pull the fuse and look to see if its blown, and if you can't see then check continuity with an ohm meter.
  9. grasswhacker

    grasswhacker LawnSite Gold Member
    Messages: 3,873

    I had a similar problem and re did the connections at the 7 way plug. Eventually I replaced the lights and the wiring and have not had a problem since. I doubt if it is a fuse, but it is a connection somewhere in the wiring. IMO
  10. hosejockey2002

    hosejockey2002 LawnSite Bronze Member
    Messages: 1,195

    I had exactly the same problem with my '05 2500HD. The lights on the truck worked fine and no fuses were blown. The dealer replaced the turn signal flasher under warranty. I know that sounds goofy, but it fixed the problem. Is your '03 still under warranty?

Share This Page