Trailer Running Lights

[timswi]

Guys,

Yesterday coming home from camp my trailer running lights stopped working (parking lights) -- my brake and turn signals work fine. Rice trailer with LED. What do you think--Ground possibly?

Picked up a screw and destroyed a tire too--Not a great day to say the least.

 

[zing]

I don't see how it could be the ground if the brake and signals are still working. Usually there is just one ground point for each light housing, which grounds the running, brake and signals on that side. Especially since you say lights, so that would mean they didn't work for light housing on both sides. Would be odd for both of the housing grounds to fail at the same time.

I would think it is more likely that the connection from your trailer to truck jack wasn't good for that wire. Did you give the connector a good jiggle and make sure it was seated properly? It is possible for a single wire to corrode or come loose, either at the trailer connector or in the female coupling on your truck.

 

[timswi]

I'm going to check the connector (got home in the dark)..That is odd. The tail light running lights and all the side markers are out. They were on when I pulled out of camp then suddenly shut off--Lights on the truck are working.

 

[Diggin It]

Running and marker lights should be on the same wire as the tailights. Start tracing wires and you may find a break in that line just off the connector on the trailer side.

 

[timswi]

Running and marker lights should be on the same wire as the tailights. Start tracing wires and you may find a break in that line just off the connector on the trailer side.

Thanks--I hope that's the case.

 

[zing]

I'm going to check the connector (got home in the dark)..That is odd. The tail light running lights and all the side markers are out. They were on when I pulled out of camp then suddenly shut off--Lights on the truck are working.

Yeah, the running and side markers should be the same wire, probably just loose at the jack which may have vibrated a bit loose while you were driving.

If it is the actual wire, it is most likely near the connector and it is easier to troubleshoot the trailer end first. I had a bad connection that made my brakes disconnect/reconnect randomly while driving. I tried re-seating all of the connections on the trailer coupling but it made no difference. Turned out the silicon in the truck jack end had mostly been washed out, so it was starting to corrode a bit. I replaced the truck jack and that solved it.

 

[Scrambler82]

Running and marker lights should be on the same wire as the tailights. Start tracing wires and you may find a break in that line just off the connector on the trailer side.

I would start at the front of the trailer checking for cracked or broken wires, bad connections, and/or bad Connector.

Check for corrosion too, and although cleaning connectors may fix the problem for the short term, corrosion can cause future problems.
Cracked wiring and poor wire connections can cause problems in the long term.

How old is the trailer ?

 

[hawkeye08]

unplug trailer, check for running lights at connector on truck, if you have it there, then you have problem in trailer wiring.. if all the running lights are out, likely in the connector on trailer side..

 

[timswi]

I would start at the front of the trailer checking for cracked or broken wires, bad connections, and/or bad Connector.

Check for corrosion too, and although cleaning connectors may fix the problem for the short term, corrosion can cause future problems.
Cracked wiring and poor wire connections can cause problems in the long term.

How old is the trailer ?

About six years old.

 

[George2615]

As Hawkeye says, check the trailer plug on the truck for running lights. If none then you may have a blown fuse. All my trailer lights have fuses separate from the truck fuses. If all your plug terminals work then start at the trailer plug.

 

[Scrambler82]

About six years old.

Six years doesn't sound like the wiring should a problem, unless you have done something different in the last few months or so !

Start at the truck connector, verify 12 volts is at the connector for each function, then process backwards and find out where the power goes away.

Do you have fuses as suggested !

Luck to ya, wish I was there, I enjoy wiring problems.

 

[Diggin It]

There are test plugs available at many places that sell trailer parts and accessories to test the vehicle side.

 

[flyerdan]

Most trailer light problems are corrosion / debris in the connector; if it has the round split pins in the socket side you might need to take a small blade screwdriver and spread them out a bit, they tend to lose connectivity over time.
I had to deal with the trailers at work all the time for this, they'd drop the plug in the dirt and mud, forget to unplug it and pull the wiring out, etc. The joys of fleet management.

 

[timswi]

Most trailer light probmr are corrosion / debris in the connector; if it has the round split pins in the socket side you might need to take a small blade screwdriver and spread them out a bit, they tend to lose connectivity over time.
I had to deal with the trailers at work all the time for this, they'd drop the plug in the dirt and mud, forget to unplug it and pull the wiring out, etc. The joys of fleet management.

I'll check that too--I have never ripped the plug out or left it on the ground--I usually semi cover it and point it towards the ground to keep the weather out..I do use this trailer fairly heavily though.

 

[Morning Wood]

I’ve never owned a trailer with decent lighting. Best bet is to track down your wire as has been stated, but to also plan for a rewire where every light has there own dedicated wire with ground that runs back to a junction box. I did that with my boat trailer finally 3 years ago and it has been fine ever since. Only problems I have are with my actual lights.

 

[nikerret]

I had a light come disconnected and the power hit the trailer-now, no parking or clearance lights. The brakes worked fine. The power from the back of the light hitting the trailer blew the fuse, in the truck. Plugged the light back in, replaced the fuse. All was well. Check that a light hasn’t come unplugged.

 

[grsthegreat]

On all 3 of my rigs i tore out the aftermarket crap the dealer installs and installed a factory plug. Most newer rigs have dealer available plug and play trailer plug adapters for their trucks. They don’t rely on the crimp thru connectors. I also installed the combination 7/5 wire plug assemblies to work on multiple applications. If you have to splice wires (older rigs) be sure to solder and shrink wrap all connections. Don’t use crimp splices....ever

 

[Deere Dude]

I had a light come disconnected and the power hit the trailer-now, no parking or clearance lights. The brakes worked fine. The power from the back of the light hitting the trailer blew the fuse, in the truck. Plugged the light back in, replaced the fuse. All was well. Check that a light hasn’t come unplugged.

That is exactly what happened to me. I pulled a running light assembly in the rear end and notice the plug in connector disconnected and fell onto some bare metal shorting it out. Must have been all the bouncing around. Luckily for me it was the first light I checked. Love LEDs. Plugged it back in and all was good.

In this instance I was on a long trip and the lights stopped working in a rainstorm and going through Nashville. My wife was following me with a car so I never noticed the lights were out because there are so many reflectors on the trailer I probably didn't need them anyway. I noticed they were not on when we got home and hour later.

 

[zing]

plan for a rewire where every light has there own dedicated wire with ground that runs back to a junction box. I did that with my boat trailer finally 3 years ago and it has been fine ever since. Only problems I have are with my actual lights.

I did the same thing after the third time the ground on my utility trailer corroded and stopped working. Haven't had a problem since.

Honestly that should be the standard. With the cost of a trailer, the little bit of extra wire they are saving can't make that much difference.

 

[Fallon]

On all 3 of my rigs i tore out the aftermarket crap the dealer installs and installed a factory plug. Most newer rigs have dealer available plug and play trailer plug adapters for their trucks. They don’t rely on the crimp thru connectors. I also installed the combination 7/5 wire plug assemblies to work on multiple applications. If you have to splice wires (older rigs) be sure to solder and shrink wrap all connections. Don’t use crimp splices....ever

Crimp connectors are fine... if you are using the right ones. Weatherpack, Deutch, possibly even high quality heat shrink red/blue/yellow ones. The cheap hard plastic red/blue/yellow ones are crap that will make your life ****. They barely work inside in dry spaces.