Turn signal wiring on 31 BHS

[ReconMarine]

Traced the lack of a left turn signal on trailer, 31BHS, to "somewhere between the connection box on trailer and signal"...

Power to tail light but nothing to signal wire. Electrical tester showed no power to turn signal wire.

Okay, so here is the real question...has anyone ever pulled a wire through a trailer or how in the heck do I get to the wire....it appears to be under the insulation.

 

[RoyBraddy]

I would test the truck side first to make sure the turn signal is there. I sometimes get my turn signals not working or no marker lights etc and the problem is a bad connection at the trailer plug. I will squirt some WD40 in the connector and mover it around good two or three times and the lights start working again.

I also have one of these trailer connector light adapters that will test the truck side to make sure a fuse hasn't blown or whatever... I got mine from AMAZON. They are also available from ETRAILER

Roy Ken

 

[ReconMarine]

Tried that, all good there

 

[Threebutchers]

Have you tested for power on both sides of the splice at the tailight fixture? They typically use cheap insulation slice crimps - and personally - I don't trust them.

 

[3'senough]

Traced the lack of a left turn signal on trailer, 31BHS, to "somewhere between the connection box on trailer and signal"...

Power to tail light but nothing to signal wire. Electrical tester showed no power to turn signal wire.

Okay, so here is the real question...has anyone ever pulled a wire through a trailer or how in the heck do I get to the wire....it appears to be under the insulation.

I have and it can be easy depending on the access you have. I used a metal wire snake to do it numerous times, but your challenge is going to be the rear wall access. Did you check the ground? Are you sure it's the hot side? If it's a ground then you could simply run a short wire down to the frame. Make sure your testing with the meter grounded to the frame as bare metal as possible for confirmation. If your testing just in the light socket it might not be accurate.

 

[ReconMarine]

tried them

Power to the right and left sides, all good grounds but no power to the left turn signal only. Plenty of power from the truck (tested and verified) and from the trailer plug in to the connector box..

Tester lights at all connections except left turn signal....

 

[RVhiker]

It sure sounds like that you have isolated the problem to be the trailer wiring to the affected bulb. If the bottom of your trailer is accessible you might be able to trace the wire and find the break. If the bottom of your trailer is covered with Coroplast, you could open it up, but that is no small task. Somehow you gotta find the break or run a new wire. I think if I had this issue I'd opt to run a new wire, and to run it from the last known good point to the affected bulb. How to get the wire there would be the question for me. You might be able to get the wire to the rear by zip tying the replacement wire to components under your trailer.

If that is possible, you gotta get it up to the taillight. My trailer is hard-sided. Installing 6" of new wiring for a new license plate holder and light was a major hassle - aluminum framing was in the way. I could connect to the old wire that needed to be extended by removing the taillight; I then drilled a hole into the interior of the trailer and routed the wire inside and then back out to the new license plate holder. The interior routing of the wire I hid with a standard switch plate cover. All of which is to say that the easiest way to route the new wire may be on the inside in some plastic conduit cover.

Jayco's schematics of the rear wall of my trailer showed some 1" by 1/2" square plastic tubing that is used for wiring conduit. Such a Jayco drawing of your rear wall might be helpful.

Also: for my trailer, the taillight wiring runs from the front to the right taillight to the left taillight inside a plastic conduit in the wall. Another suggestion would be to remove the right taillight and see what you can find out; maybe the break is accessible there.