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Lakejumper's avatar
Lakejumper
Explorer
Jan 05, 2018

Help! Issue with No Interior or Exterior Lights on Trailer!

My nephew is currently towing his travel trailer back to Colorado from California today and realized that he had no nighttime running lights on the trailer when he switched them on. The interior lights inside the trailer don't work either. He was hooked up to shore power while visiting our family for the holidays. Having previously owned towable RVs, my first thought is that his battery is bad. But then I thought that the outside running lights would work anyway. He went to Napa Auto parts and they checked for power at the plug from his Chevy Traverse tow vehicle and said that it had 14.4 volts. Any ideas? He is stuck in the parking lot several hours from us and can't tow it to a park for the night. Should he start with replacing the battery?

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  • Lakejumper's avatar
    Lakejumper
    Explorer
    Jan 05, 2018
    Thank you for the quick responses! He checked the ground at the hitch and it appeared to be okay. He is towing with a Chevy Traverse and is going to check the fuses on it next. He made to a KOA campground for the night which is good news!
  • enblethen's avatar
    enblethen
    Nomad
    Jan 05, 2018
    Does the TV have fuses under the hood to power lights?
    Make and model of TV?
  • GordonThree's avatar
    GordonThree
    Explorer
    Jan 05, 2018
    Oh to add, having 14.4v at "the plug" just means the charge line is working for breakaway battery. No impact on running lights or signals.
  • GordonThree's avatar
    GordonThree
    Explorer
    Jan 05, 2018
    DownTheAvenue wrote:
    No, the battery on the trailer has no effect on the trailer running lights. They get their power directly from the to vehicle. If none of them are working, I would check the ground first.


    X2, two separate systems. Even the ground is separate, at least on my trailer. Bargman cable ground is connected to the frame near where the cable connects to my trailer, at a junction box for lights, brakes, etc.

    TV and trailer should have enough common ground for lights just through the hitch.

    Follow the Bargman cable to it's junction box. Have someone in the truck press the brakes, measure voltage on brake line. Measure voltage on stop light line. Do the same for others.



    Put a 10a fuse across the 7way plug, disconnected from the SUV. Running lights should come on
  • DownTheAvenue's avatar
    DownTheAvenue
    Explorer
    Jan 05, 2018
    No, the battery on the trailer has no effect on the trailer running lights. They get their power directly from the to vehicle. If none of them are working, I would check the ground first.

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