Trailer Lights Nightmare

Jdog

Member
Installed brand new trailer light kit today and the passenger side works great but the drivers side trailer light stays lit like the break is on and the blinker does not work>?

Checked all wiring, checked the adapter to make sure the pins are in the right place, removed the trailer wire harnes to the suv, made sure all the pins are in the correct place with the adapter, ground was loose, fixed it, ground had broke away from the trailer to that I had just put on when I took it to the store to get some dip, Fixed that also. sitll no dice, messing with the wiring inside the light that stays lit, seems fine, turned on hazzard lights 5 times still nothing.
sitting here with what's left of my hair in my hand that I pulled out.

:sad::cry:
 
what is the suv?? some truck brands require a spliter from that dealer to make things work right?
 
Do you have a test light? Seems that you have power on the connection at the suv. You need to work from the light forwards until you find where the short is. What connector do you have, 7 way round or 4/5 flat?
 
First, make sure it's not the fixture. Switch it with the one that does work correctly. If it stays the same it's in the wiring, if not then it's in the fixture. Once you have that resolved, take a test light and check each wire to ground of your trailer to make sure there's no short. If there's no short then it's in your plug.
 
SUV = 1999 Ford Expedition 5.4L V8
My cousin has the tester and he said he would come by today and check it for me.
 
well, I had thought that also so I switched them and it didn't even light up.


Are these LEDS? If so they may be miswired inside and has the ground reversed with one of teh tail lights(seen it before). Or you don't have a good clean ground going to the lights and they are backfeeding.
 
make sure you have a good ground from your truck to your trailer, grounding thru the trailer ball doesn't get it. take a jumper wire and ground the trailer to the chassis of the truck, see if that helps, if it does, start looking at the white wire
 
make sure you have a good ground from your truck to your trailer, grounding thru the trailer ball doesn't get it. take a jumper wire and ground the trailer to the chassis of the truck, see if that helps, if it does, start looking at the white wire

Totally agree...Always a good idea to look at the ground first. And you MUST wire the white wire directly to the trailer.. the trailer ball is a great way to get a poor ground.
But he said that the one side works great, so that doesn't sound like a bad ground at the hitch. It "might" be a bad ground at the trailer light itself, where the pigtail wire from the light gets put over the bolt, but I tend to doubt that also. I think Ferm might be on to something with the miswire internally, which is why I said to switch lights and see if that solves the problem. If it does then you know it's the light and not the wiring. If it doesn't then you know it's in the wiring somewhere.
 
The lights connect to ground thru the nuts(one of /both of) that mount it to the metal trailer. Once the nuts get rusty, you lose ground. You can try running a ground wire all the way from the white wire to the nuts. I have had success with that approach in the past

Now, you say they are brand new....

Since all trailer lights are made in China, overtightening that nut causes the bolt to spin and ground (internal to the light) to be lost or intermittent.

Solution, THERE IS NONE. TRAILER LIGHTS SUCK!:fight:

Get used to it. You're a boat owner now...


P.S. Once you think you have it fixed, try turning on your headlights and check again.
 
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i used to work at a u-haul dealer and i have hooked up hundreds of trailer lights and skunk is on the money. bout the time you get them working, check again and there gone. i am on my third set of leds, get about 3 years out of them. to overcome the ground issues, i use a 100 extension cord for trailer lights. cut to length and use the 3 wires for light, signal/brake, & ground.
 
Everyone has their own solution to the problem of corrosion on the boats wiring. I usually solder all my connections, then shrink wrap them. Lately I've been using the wire connectors from Harbor Freight that as they shrink they seal at the same time. They seem to be working good. I'll let you know how good (or bad) in a couple of years.

Now, back to the problem. I'll try and make this simple. Skunk is correct, the nuts spin down onto the pigtail wire coming out of the light that usually has an eye connector attached to it. The eye connector usually is fitted over and around one of the two bolts that come from the light and are set into the plastic on the back of the traller light. When you fit the light to the trailer mount you push the two bolts through the two holes in the mount, then you slide the wire over one of the bolts. When the nut makes contact with the wire it squeezes it between the nut and the metal of the trailer light mount and makes an electrical connection to the metal of the trailer (ground) Since the lights are new, that means the bolt and the nut are new and don't have any rust or corrosion on them. So either the hole or the area around the bolthole is rusted and preventing a good ground (doubtful since the nut usually scrapes away enough rust to make a good ground) or the light is faulty or there is a problem with the wires somewhere. In all cases, since the light on the other side works great, a simple switching of the right and left lights will be enough to determine if the light itself is faulty or if the wiring is faulty.
If the light that wasn't working on the one side suddenly starts working on the other side, you know the light fixture is ok and you have a wiring problem. Quick and simple...the whole test should take no more than 10 minutes, 5 if you're fast. Simply a process of elimination. Once you determine if the light is good or bad you can work from there, but finding out if the light is ok is the first step.

or

You can take a spare 12 volt battery, or even the leads from a battery charger, and connect the ground wire to the ground of the battery, and then touch the other wires to the positive terminal of the battery to see if the light will light properly. Again, if it does you know your fixture is good and your wiring is bad. If it doesn't then you know your light fixture is bad.
 
Thank you all so much for he responces, I will switch the lights and see if that works and they are standard lights NOT Led, the led lights were 54 bucks and the ones I got were only 28 bucks. My cousin has several different testers and volt meters that I can barrow to find the problem.
I will be pissed if the light is bad, but not that much cause I got them at wal-mart lol.
Thank's again everyone!!
 
Thank you all so much for he responces, I will switch the lights and see if that works and they are standard lights NOT Led, the led lights were 54 bucks and the ones I got were only 28 bucks. My cousin has several different testers and volt meters that I can barrow to find the problem.
I will be pissed if the light is bad, but not that much cause I got them at wal-mart lol.
Thank's again everyone!!

http://www.harborfreight.com/one-pair-submersible-trailer-led-lights-94137.html

I use them on all my trailers. Nice and bright, submersible and cheap. Simply put, they work. Sealed units, nothing to corrode except the wires outside of the lights. I'll never go back to the old fashioned type of incandescent lights.
 
:news:

I used a tester on the car harness and everything works fine, the connector on the back of the suv that the harness plugs into is bad, so I got a new one from autozone and it still didnt work, the new connector from autozone had it wired wrong inside, so I just got a male and female plug and spliced into the harness by the plug on the suv and now everything works great!!!!!

Also got my battery at autozone on the charger so /fingers crossed it holds a charge.

Thank's for all the help!!!!
 
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