We ran into a problem with our 2016 Winnie Drop 1760 that was almost intractable. Because the turn signals and running lights all share a common ground that snakes through the cross members all the way to the circuit box that distributes the 7 pin connection from the tow vehicle, any faults in the wire will cause the turn signals to flash the clearance lights when there is power to the running lights. In other words any time you run and your vehicle running lights come on.
It turns out that the white wire was the culprit. We had to bypass it because it had developed a fault most likely caused by how the wire is threaded along the frame rails where the cross members pinch the wiring.
It is common to have ground faults that cause issues with trailers and even though the brake application wire circuit is fine and on a different circuit as it should be, the brake lights and therefor the turn signals, which nave a common ground that is doubled for the clearance lights, can cause weird issues if one of the ground wires is faulty. The voltage doubles back from the turn signals or the brake light into the clearance lights and causes them to flash when either you put on the brake or put on a turn signal. Rather annoying making people hit the brakes when you put on a turn signal and your trailer lights up from behind like a carnival.
We stopped moving it at night because of the issue and got some real dirty looks from a few truckers and other vehicles on the road a few times especially when changing lanes and the rear clearance lights flashed like a Christmas tree in heat!
The solution was to isolate the brake and turn signal ground and replace it to the common ground bus in the box where the wires meet at the front of the trailer. What is really annoying is that Winnebago uses cheap 16 gauge for the common ground to the back of the trailer and pinched the crap out of it during manufacture. I guess that the flex in the frame at the cross members caused the skinny ground wire to fail.
On our Winnie the power for the left is the red wire, power for the right is the brown and the greens are for both the rear clearance lights and the running lights at the back and side fender lights as well as the upper clearance lights at the roof of the trailer. The front clearance lights are on a different circuit and have a different ground which is also white but not split up the way it is at the back of the trailer. The rear upper clearance is on the same wire as the tail lights and the rear lower side lights and the fender lights then connect to a different wire which runs through the inside of the trailer at the mains and into the bath room wall.
It is almost as if Mickey mouse designed the circuit as splitting the rear tail lights ground with the center ground is nuts IMO. We put the side fender lights onto the common 12 volt ground bar so that the fender lights now have their own ground that is doubled to the frame as well as the hitch wiring. The number of possible pinch points is crazy the way this trailer is put together.
So this is just a heads up for those who run into flashing clearance lights and strange behavior from your trailers brake lights/turn signals. The problem might well be a sub par ground wire that was not protected adequately and put in a place where it is bound to fail.
Anyhow the issue is now repaired but it took a long alligator clip jumper, many hours checking for ohms on all the grounds and worst of all many trips under the trailer with the rear tail lights disassembled to finally track down the fault and repair the trailer.
Now on to replacing the wheel bearings and servicing the brakes because the cost of that here in BC is insane and the waiting list at the reputable trailer service shops is almost as bad as elective surgery even for simple services like bearing replacements.
The RV dealers are having a field day and the prices they charge are the worst of all. You fart and they add 1000 bucks on the ticket!
Trailer lights ground wire issue solution.
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