Rear LED Trailer Light

[Lennyp04]

Hey guys, the rear brake/turn light on my 07 trailer isn't working properly. It lights up with the running lights and shows that it has power but does not indicate braking or turning. I'm guessing that its wiring or possibly a grounding issue but wanted to get your guys input. Thanks!

[sheckski]

Have you. Checked braking and turning at the source? I had same issue and it turned out the problem was at the truck.

[willyt]

I'm having the same issue with my 07 trailer

[Table Rocker]

Originally Posted by Lennyp04

Hey guys, the rear brake/turn light on my 07 trailer isn't working properly. It lights up with the running lights and shows that it has power but does not indicate braking or turning. I'm guessing that its wiring or possibly a grounding issue but wanted to get your guys input. Thanks!

I doubt it is a grounding issue since the ground is working for the running lights. Test the plug with a multimeter or test light and see if you are getting 12v on the brake pin. If you don't, follow the wire and find the problem.

Make sure your vehicle is putting 12v on the correct pin at the trailer/vehicle connection.

[Lennyp04]

Is it possible that it could be the truck even if the drivers side of the trailer lights are working as normal? It's just the brake/turn signal on the passengers side of the trailer that isn't working. When I turn the headlights of the truck on, the running lights for the trailer all work, even on the side where the brake/ turn signal does not.

[Table Rocker]

You basically have four wires coming from the truck (plus a possible fifth for the reverse solenoid).
Listed in no particular order
1) Common ground
2) Running lights, side markers, etc. all on one wire
3) Left side high intensity only (brake & turn)
4) Right side high intensity only (brake & turn)

If your truck lead for the passenger's side high isn't good, your trailer will have everything but the right side brake and right turn. It would be good to make sure the truck wire was good before you started in on the trailer. It might save some head scratching. Turn your right turn indicator on and use a test light to see if you can find a blinking hot wire at the plug.

If you don't have a multimeter, you can use a tester like this:
http://www.harborfreight.com/extra-l...ter-43700.html

You could also pick up one of these easy truck testers:
http://www.harborfreight.com/four-wa...ter-66526.htmlhttp://www.harborfreight.com/four-wa...ter-66526.html

Some adapters have lights as well:
https://www.easternmarine.com/index....FcIv4AodlnsAmA

[Lennyp04]

Originally Posted by Table Rocker

You basically have four wires coming from the truck (plus a possible fifth for the reverse solenoid).
Listed in no particular order
1) Common ground
2) Running lights, side markers, etc. all on one wire
3) Left side high intensity only (brake & turn)
4) Right side high intensity only (brake & turn)

If your truck lead for the passenger's side high isn't good, your trailer will have everything but the right side brake and right turn. It would be good to make sure the truck wire was good before you started in on the trailer. It might save some head scratching. Turn your right turn indicator on and use a test light to see if you can find a blinking hot wire at the plug.

If you don't have a multimeter, you can use a tester like this:
http://www.harborfreight.com/extra-l...ter-43700.html

You could also pick up one of these easy truck testers:
http://www.harborfreight.com/four-wa...ter-66526.htmlhttp://www.harborfreight.com/four-wa...ter-66526.html

Some adapters have lights as well:
https://www.easternmarine.com/index....FcIv4AodlnsAmA

Thank you so much! I just went outside and backed the truck up to our utility trailer and it did the same thing as it would when it's connected to the MasterCraft trailer. So now that we've determined it is the truck, what needs to be replaced? Just the plug or the whole wiring? It's a 2000 Chevy Suburban.

[Table Rocker]

The first thing to do is check the fuses. I don't know if that vehicle has a fuse for each wire or not, but check. I think those fuses are in the box under the hood on the drivers side.

I just checked an online manual and it looks like you have a "Left" and a "Right" trailer brake/turn fuse.

[Table Rocker]

You might check the connections for the trailer harness. It will be across the back and I think it will have a plug on each end and the trailer wiring in the middle. I would unplug all the plugs and plug them back in. See if you can find any problems. Make sure the vehicle's turn signal is working on that side.

It would have been easier to find the problem if it was the trailer wiring. That's the bad news.

[Lennyp04]

Originally Posted by Table Rocker

You might check the connections for the trailer harness. It will be across the back and I think it will have a plug on each end and the trailer wiring in the middle. I would unplug all the plugs and plug them back in. See if you can find any problems. Make sure the vehicle's turn signal is working on that side.

It would have been easier to find the problem if it was the trailer wiring. That's the bad news.

Sounds like you've had this problem before or maybe your just an electric/wiring genius!

Regardless, I will check the fuses tomorrow. It's possible that one of them could be bad. Although it might be worse that the problem is the truck and not just the light, at least I have a concrete place to start my investigation. I know I've knocked the light receptacle off on some snow banks so I may have damaged one of the wires.