Installed LED Tail Lights & OEM Clearance Lights Go Dead

[DRSMPS]

I need some help troubleshooting the installation of some new LED tail lights on my trailer. One of the kids leaned a bike up against one of the original tail lights and broke the lens. I am unable to find the same lens to replace the OEM light, but found a new LED fixture that is a near-match. So I decided to replace both rear tail light fixtures.

The new LED fixtures have 3 wires coming from them. There is a black wire (ground), a brown wire (running light +) and a yellow wire (brake lights +). Upon connecting the new LED fixtures, I ran the black wire to the trailer frame and connected the yellow and brown wires to the corresponding wires the old fixture was wired to. My brake lights work well. However, when I connect the brown wire on the tail lights all the other clearance markers on the trailer go out. The new LED tail lights illuminate but all my OEM incandescent clearance lights stop illuminating. When I disconnect the brown wire, all the other marker lights come back on.

Stumped, I called the store I purchased the tail light fixtures at. They indicate that you should not mix LED and incandescent bulbs on the same circuit and recommend that I replace all my clearance marker lights with new LED ones. Has anyone else experienced this issue when installing LED lights? If so, did you replace all bulbs on the same circuit with LEDs? Is there another way of wiring these to avoid this or is it possible my new fixtures are defective?

Thanks for any advice you are able to give in advance.

[jeepfreak]

Try them with engine running. I put replacement led tail lights on my 79 cj7 and went thru everything because they won't work when attached to the mh. Started the motor in th mh and they work. Don't know why. But give it a shot.

[mike-s]

Assuming you've got the colors/functions correct, it doesn't make much sense. If connecting the running light wire (brown) causes other lights to go out, the new lights must be pulling that line low. But if that's the case, I would expect a fuse to blow.

What brand/model are the new LED lights? It sounds like you got it right, since yellow(and green)=stop/turn, brown=running are common colors and if all that's left is black, it should be ground.

(Switched ground would be a real oddball. The signals from the TV use a common ground with all common trailer connectors, and most taillights are wired for that.)

[RoyB]

When you look at all the schematics on ETRAILER.COM on wiring up trailer safety lights the BLACK WIRE seems to be HOT +12VDC... The WHITE WIRE coming from the trailer side of the 4-pin connector goes to frame ground up near where the connector wiring is at (Tongue of trailer)...

It also shows the
Brown-Tail/Running Lights
Green-Right Turn/Brake - Remember green has an R in it
Yellow-Left Turn/Brake - Remember yellow has an L in it

It looks like the fixture gets its ground from the metal outside fixture being screwed down on the metal frame...

Check out some of the wiring drawings on ETRAILER.com to see if any of that makes any sense for you particular application.

Paperwork with the new fixture should also identify where your wires are suppose to go as well...

Roy Ken

[GordonThree]

How did you determine the polarity, did you confirm it with a volt meter? When I replaced my trailer tail light license plate holder fixture, there was an always on positive (black wire) and two switched grounds (different colors,) one for running, one for stop.

In RV land, for whatever reason, black is almost always positive.