trailer brakes locking - brake controller not recognizing

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Aug 23, 2011 | 08:55 AM

Hurricane Ditka

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trailer brakes locking - brake controller not recognizing

First post!

So title says it all.
My brake controller is not recognizing the trailer, however the brakes lock on when it is plugged in.
The trailer has a 5-pin connector, and I am using a 5 - 7 pin adapter.

Once the connector is unplugged, the trailer rolls freely. I asked a few friends who are ford diesel tech's at a local garage, and one said the trailer might be too old to be recognized by the controller..

Any help is greatly appreciated!

Oh, and the truck is a '05 f250 with factory installed controller.
Trailer is a '98...... cant remember the brand.... (g/f's trailer) horse trailer...

Aug 23, 2011 | 09:05 AM

thomabb

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My guess is something else electrical isn't working either. Get a tester and start checking all the circuits to see which one isn't doing what it is supposed to do. Sounds like you are feeding +12v constant battery to the brake circuit.

That trailer isn't too old for the controller to recognize. Electric trailer brake technology hasn't changed that much in 13 years. I have older trailers than that.

Aug 23, 2011 | 09:11 AM

miller_feed

Hook it, I'll pull it.

Joined: May 2007

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From: Grand Lake, La.

Welcome to FTE.

Have a look at this link to give you an idea where to start looking. Trailer Wiring Diagrams | etrailer.com

Aug 23, 2011 | 09:12 AM

dchamberlain

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From: Scio, OR

There were no real standards for 5 and 6 pin connectors. With 6 pin connectors it was common to get the wrong adapter and it would put the 12V feed from the 7 pin to the brake wire.

I would rewire the trailer with a standard 7 pin connector.

Aug 23, 2011 | 09:28 AM

Hurricane Ditka

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Wow! Thanks for all the info, and so quickly.

If all the other lights, and ground work great, could the 5 pin connector just be routing the connection to the wrong connector on the truck side? That was my guess, but I've never re-wired a trailer that had anything more than a 4-pin strip.

Aug 23, 2011 | 09:34 AM

Hurricane Ditka

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OH, and also. Just checking that wiring diagram miller_feed posted, the trailer had a red wire for the trailer brakes.

White
Green
Yellow
Brown (maybe black, haven't looked in few weeks)
And red.

Red was the control wire for the brakes.

The brake wire is blue on that diagram.

Now I know the color wont matter as long as it is sire correctly, but does anyone know of any common problems with routing of a red wire instead of the blue?

Just wondering, since I wont be able to check it for a day or two.

Aug 23, 2011 | 10:06 AM

dchamberlain

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From: Scio, OR

Just go to most any auto parts store or RV store and get a 7-way connector. Cut the 5 pin off of the trailer and wire the 7 pin on using the diagram in the link above. Except wire the red wire where it says to wire the blue wire. Check the ground for rust or corrosion, it's the white wire and probably is attached to the trailer frame up near the hitch. Everything should work fine.