brake or wiring issues

Is your trailer brakes working for you... Use the manual slide switch and see if that stops you and trailer without pushing the brake pedal on the truck...

I do this quick test everytime I hook up before I leave my neighbor hood...

You can use your boy scout compass up close to each wheel when the brakes are applied and see if the needle deflects on each wheel... I think the Ford OEM brake controller however has to be moving above 10MPH before the Electric brakes get DC Voltages from using the Truck Brake Pedal. Works anytime using the manual slider switch... My 2010 Ford OEM Brake controller does this at any rate...

My brakes make a low tone noise when the magnet is activated.

It is a US DOT Safety law that your brakes and on-board trailer battery are working when being towed over public roads... This is an enforceable law... This is required for the Emergency break-away trailer switch being operational...

Kinda of important to have working trailer brakes I would think...

The Ford shop can tell you if the OEM Brake Controller is working properly for a $90 minimum shop fee... A boy scout compass is just a couple of dollars...

Roy Ken

I know it is either wiring to brakes or brakes themselves. No brakes when towing.. lights all work. I tested truck with new trailer and everything worked. Would a semi trailer type shop be a good option? Or RV shop with 2 mechanics to do everything be better?

check all the wires under trailer. any disconnected..?

also many trailers do not weatherproof connectors for brakes.

many RV, auto, light truck places can do wiring repairs and testing of trailer.

or have a mobile RV repair service come to you.

The fact that you have no error when plugged into a different trailer pretty much tells you the issue is with your TT. I had a similar issue and found that one of the trailer power wires had abraded and was shorting out against the frame (ground) where the wire came out of the axle. I repaired it and added a plastic covers over the wires and the problem went away.

I had that at the beginning of the season. Replaced almost everything and finally found out it was the magnets and the wires to the magnets had burned up. The wires literally fell apart from being cooked.

If you search my posts you will find it.
Intermittenting brakes.

okay, I just saw another post about breakaway pin being pulled and trailer hooked to power causing issues with brakes..

I did have my breakaway pin broken possibly activating brakes. I cut wire at direction of shop, to take trailer to get breakaway assembly replaced. no issues on trailer then or at beginning of next trip. Now I am wondering if the breakaway pin caused this issue.. If so, I am getting angry, because yard guy broke pin... and didn't tell me.. I just found cable sitting on top of propane tank.

Since replacing the breakaway switch made the error go away, pretty safe bet that was your issue.

Was your house battery dead? Does the trailer have a separate breakaway battery that's now dead?

If the broken pin caused the breakaway switch to activate, that would cause your brake controller to throw an error, at the very least. I would also have expected you to notice other problems, like the house battery being dead, or the trailer pulling exceptionally hard like the brakes were locked up.

What is the error code

okay, update on trailer issue.. truck was giving "trailer wiring fault" error and if i touched brake controller, I got no trailer. error appeared sometime (not immediately) after I had the breakaway replaced. Did have to drive off the road to go around a tree down on way home last trip before error appeared.

Took trailer to local trailer shop (not RV shop but a commercial trailer repair shop). Less than an hour after leaving it, I got a call, they had jacked up each wheel tested the brake with power and tested the breakaway and found nothing wrong. couldn't get it to not work on any wheel. Mid afternoon, I went to pick up thinking I would have to take truck to Ford dealer for computer analysis. Mechanic jacked up and demonstrated braking and breakaway for one wheel. I then plugged my truck in to check with my truck and NO ERROR.. everything worked like it should. Trailer shop exorcised a gremlin. No real clue as to what problem was, unless the jacking up and down wiggled something. Drove home and parked trailer with no lack of connection.


anyhow, I am good now.. still don't know what happened, but happy I didn't expend tons of money chasing a gremlin and that I get to take the trailer out next weekend, since I missed last weekend due to concern over brakes.

The gremlin will return, the problem is intermittent and has not been corrected.