ford truck "trailer wiring fault"

kreid · 08-08-2016, 12:23 PM

Anybody have an issue with a trailer wiring fault coming up on the display of their ford trucks? Mine is a 2012 f250 and everything on my camper is working down to the charge line.

sailor · 08-08-2016, 12:39 PM

No problems on my 2013 F350. My first suggestion would be to check and clean both the trailer plug and the truck socket to eliminated any corrosion. Be sure the ground connection between the truck and trailer is solid. A flakey ground connection can cause lots of weird behavior. You might even try a temporary wire between the truck and trailer to see if that pin points the issue.

kreid · 08-08-2016, 01:19 PM

Quote:

Originally Posted by sailor

No problems on my 2013 F350. My first suggestion would be to check and clean both the trailer plug and the truck socket to eliminated any corrosion. Be sure the ground connection between the truck and trailer is solid. A flakey ground connection can cause lots of weird behavior. You might even try a temporary wire between the truck and trailer to see if that pin points the issue.

I appreciate the quick reply, when I got the camper 2 weeks ago I noticed the 7 pin wiring plug had been dragged pretty significantly behind the truck by the previous owner. I went ahead and changed it out for a new plug (male end) so I know all of the connections are good there. Didn't have this issue with previous travel trailer I sold two weeks ago nor with my utility trailer. I am pretty sure it isn't the truck so that lead me to the trailer. The battery was shot so I bought and installed a new battery,still has wiring fault. I'd like to check the junction box that the 7 pin wiring harness comes out of but I can't locate it. It was behind the pin box in my last two 5th wheels but on this one (365bhs ) I can't see it. I'm afraid I'll have to drop the fiberglass sheeting that's under the camper by the pin box to find it. Uggghhh 😩

**Mustang65** · 08-08-2016, 01:38 PM

Take a Volt/Ohm meter and check out all your connections on the trailer cable. You can make a shorting plug and test the trailer lights out at the plug, just be careful not to short the 12Volt pin to the ground one.

Don

jasum · 08-08-2016, 03:00 PM

My truck is older than yours, but mine does that and it seems to be a truck ground issue on mine.

eldermike · 08-08-2016, 04:00 PM

The chassis ground at the front end of the camper located somewhere on the A frame is notorious for corrosion.

chlinthi · 08-08-2016, 07:18 PM

I've seen this twice on my 2011 F250 and both times it was just because the plug was a little loose.

Another way to test if its on your (truck) side or the trailer's would be to just temporarily hook your truck up to someone else's trailer and see if you get the same error message.

Marine71-76 · 08-08-2016, 07:22 PM

We have a 2008 F450 and pulled a 2007 Cameo for 9 years without this occurring one time. We picked up the Jayco Pinnacle in April and did a few small (less than 4 hour trips) and never had a problem. We went from Cincinnati to Virginia Beach and before we hit the tunnel, it came on. Pulled over & double checked everything and it was fine. Called Coach-Net (which is a joke) and the mobile guy came out & looked at the wiring harness in the kingpin and then checked the truck - guess he was in a hurry because he forgot to ask that the brake controller be activated and said it was the truck. Finally found a Ford Dealership who could look at it and they put it on a simulator for several hours - nothing.

On the way back, wife contacted both Jayco and Lippert - Lippert said to find someone who could check it out before we hit the mountains and Jayco says it is a known issue with Ford's integrated brake controller (ICB) because their wiring is NOT compatible with the Ford ICB. We found a trailer (horse/utility) business that works with Lippert. Final outcome - nothing wrong with trailer or truck.

Not sure how Jayco can have incompatible wiring.

There is another post on this several weeks ago.

Rustic Eagle · 08-08-2016, 08:35 PM

There are issues with GM's system as well....., not an uncommon subject on the GM truck forums.

Another possible area to check is the FW's brake wiring. On GM trucks the dash display for "Trailer Connection Status" is tied directly into the trailer's electrical brake system wiring only (not turn signals, running lights, etc.).

As mentioned a faulty FW (or TT, HTT, etc.) frame ground is a possibility, but a bad ground wire in the actual trailer brake system wiring can cause a 'fault', as well as a faulty brake magnet.

GM has gone as far as saying that the 7-pin connection "plug" from the trailer being towed should be manufactured by the same OEM that GM uses.

Bob

klassic · 08-08-2016, 08:56 PM

Do you have solid braking when you slide the controllers manual slider?
Does braking force increase when you turn it up to 10?

I don't know where the junction box is on your rig, but on the NorthPoints they are wire nutted behind the light beside the hitch (if you have one)

citgodan · 08-09-2016, 10:32 AM

X2 what Sailor stated. My 2012 F-150 did the same thing. I lubed up both the truck's 7pin and the trailer connecter's side with WD40, attached and reattached a few times and no more fault issues, or flickering lights on the trailer.

TXCrew · 08-10-2016, 01:55 PM

We have a 2015 Ford Explorer. On our way from Texas to Yellowstone, the trailer locked up its breaks when we were trying to leave a campground in Kansas. We unplugged and plugged back in the trailer wire, which caused the brakes to unlock but the Ford would not recognized the trailer. We took it to a commercial vehicle place which cleaned the plug. The Ford then recognized the trailer but a "Trailer Brake Module Failure" warning appeared and remained.
The module was replaced, although the part had to be ordered. Luckily, for us, the dealership in Kansas was great. They requested that another dealership overnight the module to them, and we were back on the road the next day. Otherwise, it could have taken 2 weeks to order the part.

Cdash · 08-12-2016, 01:34 PM

This may not apply, but one thing I noticed on our camper when we got it was that the brake wires at the trailer axles were in contact with the springs. I would expect if that is common, it could be pretty likely that the spring could wear through the insulation and cause issues.

May not be the cause, but may be worth checking.

kreid · 03-06-2017, 08:54 AM

Quote:

Originally Posted by Marine71-76

We have a 2008 F450 and pulled a 2007 Cameo for 9 years without this occurring one time. We picked up the Jayco Pinnacle in April and did a few small (less than 4 hour trips) and never had a problem. We went from Cincinnati to Virginia Beach and before we hit the tunnel, it came on. Pulled over & double checked everything and it was fine. Called Coach-Net (which is a joke) and the mobile guy came out & looked at the wiring harness in the kingpin and then checked the truck - guess he was in a hurry because he forgot to ask that the brake controller be activated and said it was the truck. Finally found a Ford Dealership who could look at it and they put it on a simulator for several hours - nothing.

On the way back, wife contacted both Jayco and Lippert - Lippert said to find someone who could check it out before we hit the mountains and Jayco says it is a known issue with Ford's integrated brake controller (ICB) because their wiring is NOT compatible with the Ford ICB. We found a trailer (horse/utility) business that works with Lippert. Final outcome - nothing wrong with trailer or truck.

Not sure how Jayco can have incompatible wiring.

There is another post on this several weeks ago.

Have you had this happen anymore? Do your brakes work as designed still?

Marine71-76 · 03-07-2017, 08:40 AM

Since the dealership fixed the wiring on the trailer - yes, there was a wire on the door side front axle that was broken - no problems. We have been to Gatlinburg and back without any issues.

glitelover · 04-24-2019, 02:22 PM

Quote:

Originally Posted by Marine71-76

Since the dealership fixed the wiring on the trailer - yes, there was a wire on the door side front axle that was broken - no problems. We have been to Gatlinburg and back without any issues.

I know this is a very old thread, but we just had almost the same thing happen to our 2017 North Point.

Fortunately, DH was within an hour on the interstate of our dealer, and they took it right in.

Unfortunately, it took them 4 hours to find the faulty wire (they didn't even know where the junction box was - I had to send DH a photo to show them), and we got charged a pretty good chunk of change for the repair - all labor.

Pretty scary when you're fully loaded and headed down the highway to realize you don't have trailer brakes.

Jayco said they don't cover brakes under warranty and referred us to Lippert, but this was a WIRING issue, not the brakes themselves, so I'm confused.

Did your dealer do any better than ours?

Thanks.

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