Tail Light Wiring Help

[Lhinkle114]

Hello, can someone please help me I was attempting to replace a tail light on a 2019, 3791RD Montana and somehow screwed up the wiring and not sure how it all goes back together. I’ve looked at the wiring charts and I’m a little confused so I still know where to start. I am attaching pictures of the light and the wiring off the camper for both sides hoping somebody there with more knowledge than me can help.

Thank you in advance
Larry

[Lhinkle114]

My right light wires on the RV are:

RV. To New tail light
Two white. ? Two white
Two green/white. ? Two black
Black. ? Red
Yellow. ?

My left rv wires are:
RV. To. Good connected left light
Four white. To. Two white
Two green/white. To. One black
Two Yellow. To. One black
One red. To. One red

My new right tail light has:
Two white
Two black
One red

Thank you in advance
Larry

[BB_TX]

You can check with a volt/ohm meter set to resistance, but on your new light assembly the two black wires are probably common and your two white wires are probably common.

Someone will be along shortly, I am sure, with a wiring diagram. But you can be absolutely sure of the trailer wiring by using a voltmeter. Connect your cord to your truck and turn on the lights. Using your meter, touch the meter ground lead to the inside of the white wire connector, then touch the positive lead sequentially to the inside of the other wire connectors until you see 12 volts on one of them. That is the tail light. Turn your lights off and turn on the turn signal for that side. Again using white for ground, touch the positive meter lead to the other connectors until you see 12 volts turning on and off. That is your stop/turn light. Then you can match those to the labeling in the light assembly.

Looking at the bottom picture, I am guessing yellow and green are used for connecting the clearance lights to the tail light wiring.

[Lhinkle114]

So if I understand you correctly
The two white wires on the light go to the two white wires on the trailer and red wire on the light goes to the black wire on the trailer. Then the other two black wires on the light go to the green/white wire and yellow wire. Does that sound right?

[Daryles]

Here's a picture of my RIGHT light.
The LEFT light will have a duplicate wire that crosses over to the RIGHT light. That's why there is two of each in the left junction.

[BB_TX]

Originally Posted by Lhinkle114

So if I understand you correctly
The two white wires on the light go to the two white wires on the trailer and red wire on the light goes to the black wire on the trailer. Then the other two black wires on the light go to the green/white wire and yellow wire. Does that sound right?

That sounds right. And seems to match the picture of Daryles above. Using a meter would certainly verify that. Unfortunately uniform color coding is not used throughout and it ends up with mix of colors connected together.

[Lhinkle114]

That fixed it, thank you for all the pictures and help I couldn’t of done this without you guys. This forum has the best group of people you could ever find.

[Daryles]

When you put it back on, do NOT use the foam material. Put it directly on the wall. Once fastened down, Caulk all the way around it. Actually put a little dap of Caulk under the screw head.
The lights leak because of the foam material. Keystone put out a TSB to remove the foam and Caulk around the perimeter.