Wiring fault on trailer - TheDieselGarage.com
Thread Details Posted by John844, this thread has received 5 replies and been viewed 1209 times.

LinkBack Thread Tools Display Modes
post #1 of 6 (permalink) Old 09-24-2007, 09:43 PM Thread Starter
Junior Member
Join Date: Aug 2007
Posts: 21
Points: 106
Thanks: 0
Thanked 0 Times in 0 Posts
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?
John844 is offline  
Sponsored Links
post #2 of 6 (permalink) Old 09-25-2007, 12:03 AM
Senior Member
Hydro's Avatar
Join Date: Dec 2008
Location: Lakewood, CA
Posts: 307
Points: 25,217
Thanks: 24
Thanked 40 Times in 29 Posts
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.
Hydro is offline  
post #3 of 6 (permalink) Old 09-25-2007, 01:24 PM Thread Starter
Junior Member
Join Date: Aug 2007
Posts: 21
Points: 106
Thanks: 0
Thanked 0 Times in 0 Posts
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?
John844 is offline  
post #4 of 6 (permalink) Old 11-14-2007, 01:35 PM Thread Starter
Junior Member
Join Date: Aug 2007
Posts: 21
Points: 106
Thanks: 0
Thanked 0 Times in 0 Posts
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.
John844 is offline  
post #5 of 6 (permalink) Old 11-14-2007, 03:52 PM
Join Date: Dec 2008
Posts: 43
Points: 10,354
Thanks: 4
Thanked 0 Times in 0 Posts
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.

2008 F350 Crew Cab 4WD 6.4 Spartan Tuned
Dav700 is offline  
post #6 of 6 (permalink) Old 02-08-2008, 04:30 PM
Roach's Avatar
Join Date: Dec 2008
Location: Illinois
Posts: 89
Points: 1,871
Thanks: 0
Thanked 2 Times in 2 Posts
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.

2008 F-350 Lariat Dually, 4X4, Long Bed, Sirus Radio, Prestige Remote Start/Turbo Timer, Retrax Bed Cover, Power Tailgate Lock, Pillar Guages, Pyro, Boost, Trans Temp., chrome door handles, chrome fuel filler door.
Roach is offline  
Sponsored Links
Gear in this thread - Powered by O'Reilly Auto Parts

Quick Reply

Register Now

In order to be able to post messages on the TheDieselGarage.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome