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No power to 7 pin trailer connector

Discussion in 'Chevy Silverado Forum (GMC Sierra)' started by ergo10241, May 24, 2013.

  1. ergo10241

    ergo10241 New Member

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    Hello, I have 1999 Chevy 2500, with a 6.0 liter engine. It came with a factory towing package. This year I have no power to the trailer connector. I haven't hauled anything in two years. I have tested the wires along the frame up until the reach the cab of the truck and have no power. I also found a ground wire that was rusted up pretty bad on the frame. I grinded the rust off, and made sure it was getting good connection, but still nothing. Any help is greatly appreciated.
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  2. Enkeiavalanche

    Enkeiavalanche Moderator

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    Here we go again.. Look under the hood next to the fuse box or Battery You should see a wire tied up maybe a fuse able link hook that up and you should have power.. Check the owners book first to make sure it's there..
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  3. SurrealOne

    SurrealOne Former Member

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    You can also search the forum, as this has been asked and answered a lot. With it being Memorial Day weekend in the United States, you may get faster answers by finding existing threads on the topic and reading through them, as people are out and about doing what they do on this particular long weekend that falls early in spring.
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  4. BigBlueLB756

    BigBlueLB756 New Member

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    Let's see. This is a '99 truck that he's been pulling a trailer with in the past, so voltage has been there before. So, since the wiring has been checked, here's a list of the relays and fuses involved with the TRL wiring:

    In the CENTER INSTRUMENT PANEL UTILITY BLOCK, check the trailer brake wiring relay (top row, 2nd from the left).

    In the UNDERHOOD ELECTRICAL CENTER (fuse box), check the fuses for STUD #1 (trailer wiring feed; the most likely suspect), STUD #2 (trailer wiring brake feed), TRL R TURN, TRL L TURN, and TRL B/U.

    When it's an electrical problem, check EVERYTHING related. A wire could be hooked up wrong.

    Here's the Owner's Manual:
    http://www.silveradosierra.com/down...rs_manual/1999_chevrolet_silverado_owners.pdf

    Good luck.
    And welcome to the forum.
    #4
  5. j cat

    j cat Active Member

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    This is the way it goes most times with this issue.

    trailer has not been used over the winter. rats etc chew up the wiring. then the owner hooks up trailer then the shorted chewed up wiring shorts out the power threw trailer harness.

    I would check all fuses but first check that the trailer wiring is secure and not shorted out.
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  6. ergo10241

    ergo10241 New Member

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    I have already checked all of the fuses, they are all good. I am getting power to all the fuses. The trailer lights do work, I connected the trailer to a different truck and they all worked. I will check for the wire by the fuse box. Thanks for the suggestions.
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  7. SurrealOne

    SurrealOne Former Member

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    Another thing to consider is the fact that the 7-spade connector is just an interface to a plug that's on the back-side of it. You might disconnect the plug from the back of the 7-spade connector and make sure the contacts are clean on both sides of the 7-spade connector AND on the plug that you disconnected from it. (Apply contact cleaner if unsure.)

    Such items at the aft end of the truck tend to get dirty over time. It could be as simple as cleaning the contacts...
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  8. ergo10241

    ergo10241 New Member

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    I did find a blue wire with a fusible link in the same bundle of wires that runs down with the wires that go to my connector. Would that be it? I don't know much about wiring. I have power between the link and the fuse box but nothing after that.
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  9. j cat

    j cat Active Member

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    the fuse able link is a wire fuse. when good it is a solid electrical conductor. when current flow is excessive it will melt open. check first why it has blown. something caused this.

    after finding the cause [most likely defective trailer wiring] replace with a regular fuse / socket kit. this way if it blows again you can replace the fuse quickly and cheaper.

    you will need to make the fuse waterproof when its all corrected. tape up this with some electrical tape...
    #9

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