UHAUL TRAILER 4 PIN

Discussion in 'Wiring' started by kenbust, Sep 14, 2016.

  1. kenbust

    kenbust New Member

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    on the connector the
    RIGHT light ALWAYS on

    anyone have issues with UHAUL TRAILER LIGHT POWER MODULE ?


    checked trouble shooting guide

    GROUND WIRE - disconnected, cleaned, reconnected
    LIGHT STILL ON

    T CONNECTOR - disconnected, cleaned, reconnected
    LIGHT STILL ON


    seems like the constant signal is coming from UHAUL TRAILER LIGHT POWER MODULE

    thinking of replacing the UHAUL connector or removing it completely....

    advice?
     

    Attached Files:

  2. tzmartin

    tzmartin Well-Known Member

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    I'd remove it. What does a module really do in a 4 pin set up? A trailer harness would be plug and play direct from your rear lights. Just get one on ebay that matches your TV. You could bypass but i don't know the wiring diagram. I suspect that brake and tail are one and the same. Don't quote me.
     
  3. eoleson1

    eoleson1 Well-Known Member

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    Check the power coming in to the module. If you have no power coming in to it, but power coming out of it, you've got a bad module. When you replace the module, get rid of all those scotch-lock connectors too.

    The module is necessary for any vehicle that has separate turn and brake lights. It combines the signals from the TV to direct them to the combination light on the trailer.
     
  4. Customer

    Customer Well-Known Member

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    I have had tail light converters fail although I have never had one from Uhaul. When mine failed it appeared to be heat related, when high temperatures were present or the lights were on for many hours the left tail would stop working.

    You MUST use a tail light converter. I like the fact that yours uses a power wire to operate the lights rather than taxing the OEM wiring. It is necessary for your vehicle due to the small gauge wires used by the OEM, they cannot carry the additional current needed for trailer lights.

    I have purchased tail light converters from etrailer and from Amazon. The ones with a power wire are more expensive than the ones without.
     
  5. ScoobyDoo

    ScoobyDoo New Member

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    My idea; back close to your trailer, plug in the light cord without letting any other part of the vehicles touch. If all lights work as they should, you have no problem. Just another example of a LED "tester" lying to you. Might check to see if the black box has a good ground where mounted.
    The use of "Scotch Lock" connectors is a indication of ignorance, or lack of pride in workmanship.
    A guy I do some work for has half dozen trailers on the street most days. After he bought TVs that had separate brake/turn lights the failure rate for the converter boxes was high enough that we mounted extra lamps on the trailers, and wired the brake light circuit to the "AUX" (what many call backup lite) on the 7 pin.
    I have heard that some vehicles need a box because the wiring to the rear will not carry the extra load of trailer lights...
     
  6. Raycfe

    Raycfe Waterford Ct.

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    Replace the module ....... and be sure to get a powered one (has battery wire). No if, ands, or buts,

    As for needing it ..... if the TV (tow vehicle) has a separate turn signal and brake light it is needed to convert the brake and signals to a combination to use on most single bulb (duel filament bulb) on most trailers.

    A powered module will not effect the tow vehicles electrical system that most late model vehicles have.
     
  7. jmcclung11

    jmcclung11 Active Member

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    I put a hitch and wire on our Santa Fe to haul a trailer with kayaks. I tested everything and all work great. I rented a uhaul trailer to bring my kayaks from Florida to Virginia. Well, the right light wouldn't work! I was pissed. I was at a buddy's house and hooked up another trailer and all worked perfectly! Moral the story is that uhaul lighting sucks!

    Sent from my Samsung Galaxy SIII.
     
  8. kenbust

    kenbust New Member

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    THANKS ALL !

    Super helpful advice & info.

    The module was installed by the previous owner, so not sure how long its been bad.
    Will replace ASAP, as I need to tow my pop up nest week.
     

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