Wiring fault on trailer - TheDieselGarage.com
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post #1 of 6 (permalink) Old 09-24-2007, 08:43 PM Thread Starter
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Wiring fault on trailer

We are getting this error after driving/towing in the rain. It does not appear when we are towing, but when we unplug the trailer and do anything that activates the right brake light. The error will go away if we plug the trailer back into either the plug in the bed, or the factory one.

The first time this happened, I thought something was wrong with the additional plug we recently had added into the bed. I re-wired the plug -- wanted to do it right anyway. Wife paid 50 bucks to have a shop wire it. Nothing was protected from the sharp edges. It wouldn't have lasted more than a couple months before shorting out. They did not put anything in a loom, or even tape it up.

I found water in the factory plug where the wiring enters the plug bolted to the hitch. After drying it out, the error went away.

This last weekend it rained again and the error reappeared. I went straight to the plug expecting to find water, but it was not full. There was moisture, but not enough to short things out. I detached the additional wiring to ensure it was in the factory wiring, and the problem remained. I did not find any other problems or the root cause, but 2 days later the error went away on its own.

I am 99.9% positive it is a water issue. I would prefer not to have to mess with the dealership until absolutely needed. They tend to give me the runaround, and especially since the error is not showing.

Any suggestions?
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post #2 of 6 (permalink) Old 09-24-2007, 11:03 PM
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Yes, same thing happened to me. The wiring harness needs changed out under warranty, don't let them put electrical grease on the fittings. There is a TSB out on this issue. The connections get corroded and fail. I forget the number right now but just tell your dealer there is a TSB for the tow hitch wiring harness and they should take care of you. I'll try to post the TSB number when I get home.
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post #3 of 6 (permalink) Old 09-25-2007, 12:24 PM Thread Starter
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Any idea what they will do with the second plug wiring that is tapped into the harness? Will they hook it back up, or just leave it for me to re-wire?
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post #4 of 6 (permalink) Old 11-14-2007, 12:35 PM Thread Starter
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Tsb #

Does anyone have additional information on this TSB? I looked in the TSB forum and did not find anything. A number or the details would be helpful when I take the truck back in.

My wife took the truck in yesterday and they spent all day looking for the problem. They claimed it was due to using the clip on wire connectors for the second plug, so they disconnected my second plug, and reset the computer. They did not replace any of the wiring harness.
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post #5 of 6 (permalink) Old 11-14-2007, 02:52 PM
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Mine was showing a fault on trailer connection when towing. Only when plugged in. Took it in and they replaced the plug and bracket under a TSB.

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post #6 of 6 (permalink) Old 02-08-2008, 03:30 PM
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Mine was doing the same thing. I took it to the dealer, and they ran the "check" to see if any codes. Found none. TSB refers to aftermarket wiring plug. Took it to the RV dealer, took out old plug and wiring, and replaced it with a new one. Now....the same thing is reoccurring, and dealer doesn't know what to do. Does the orginal factory plug need replaced? Any ideas? Thanks.

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