Hello. I hooked up the trailer tonight to test the lights...we are suppose to leave on a trip in a day or two. I turned on the headlights and my trailer lights didn't turn on...brakes, turn signals, nothing! I just happened to turn off my headlights and noticed that my brake lights now work, and I can get the right blinker light to turn on, but when I turn the left on, the right also blinks! And like I said, none of these work if my headlights are turned on.
I checked and cleaned the my 4 wire flat connection on the truck and on the trailer. I double checked the connections within the wires as they extend down the bottom side of the trailer. They are all good connections...tight.
I stuck a 4 wire tester into my truck plugin and it showed that the truck connector is working fine...
I think I have to have a bad connection...but where??? I haven't touch any of the other wiring. This was the first time I hooked everything up since last fall.
ANY ideas on what to do on my end or what to check....I WOULD APPRECIATE ANY HELP!!!
Not sure, but it sounds like you have the wiring connected incorrectly.
First of all, don't use color for connections. Test the trailer lights and determine which wire does what. In other words, find the TM or Tail and Marker light wire. Find the RT and LT wires. The ground is visibly attached to the frame.
4 way code: white is ground, Brown is TM or running lights, Green is RT and Yellow is LT.
7 way code: white is ground, Brown is RT, Green is TM and Red is LT. Easy to see the difference.
If the vehicle is correct, the trailer wiring is probably not correct. Triple check that GROUND!
From what I have read overnight, it sounds as if I've got a bad ground because of the squirrelly way the lights are working...or not working...I'm going to take the back lights off the trailer (not disconnecting the wires) and clean off the metal plate where it comes into contact with the aluminum siding. Reattach them and see what happens. These lights have worked great for the last 2 or 3 years so I know they are wired correctly. My guess is a bad ground right now...crossing my fingers and we'll see tonight when I get home...otherwise I've got to figure out something with some temp lights WITHOUT screwing them into my siding!!! Wish me luck guys! I'll need it.
Yes, could be a bad ground. WHen a ground is weak or not present the voltage will look to find a way to ground which can be through an unpowered adjacent circuit such as the taillights when using only the signal. Turning the headlights on interrupts that "ground" so then nothing works. As a temporary measure you can run a ground wire from a clean spot on the frame of the truck to the same on the trailer. Also, these old trailers were often body ground at the fixtures and years of corrosion or paint has stopped that. A jumper at the bulb socket to a known good ground can also help trouble shoot.
Ok...we left on our trip this morning. I couldnt find the problem. I even ran an extra ground from truck to trailer tongue...bare steel...nothing. So i bought temp lights, laid them on the ground, hook them to my trucks flat 4pin and when the truck headlights are on they didnt work either!!! With the headlights off the temps worked other than running lights so we will only drive during daylight using brake lights and blinkers as needed. This tells me my problem is the truck wiring not the trailer, right? The only catch is my flat 4 pin tester is telling me the truck wiring is fine...sigh.
Well...an update. I ended up attaching temp lights to the trailer and wouldn't you know it...they acted the exact same way that my trailer lights were. If my truck lights are on, they didn't work at all. Turn my truck lights off, and I got brake lights and blinker lights...but no running lights. So, we ended up going on our trip and I just made sure to only pull the trailer during daylight which was fine, we were able to get to our destination in about 6 hours. I got a family member who is an electrician and we fiddled with the temp lights and found out they were not grounded well enough and as soon as we got them grounded, they worked correctly...so...I'm going to pull my tailights and run a short stub ground wire from the base of the lights to the skin of the trailer (new hole, new screws) and see if I can ground each light separately and hopefully I will get them the regular lights working then...so wish me luck...I'm going to try this weekend.
P.S. - at one point, I was thinking that something was wrong with the wiring harness on my truck...but the family member came over and hooked his truck up and he had just tested his boat lights and they worked and guess what? The trailer lights didn't work on his truck either. So that ruled out the trucks. It had to be in the trailer.
Any time your lights work with the headlights off but go nuts with the lights on it is a bad ground a battery system will ground through the turned off lights until you turn them on now both wires become positive and nothing works right.Also another sign of a bad ground is when you turn on a turn signal and the one flashes near normal and the other side flashes dim. My guess is you need to ground the trailer skin to the trailer frame, then your ground between the frame and the the truck will complete the circuit. you may wind up having to ground the trailer skin in multiple places to cure your problem. This comes from 50 years of experience solving this type of problem. I would start by bonding the rear panel that supports your tail lights to the frame and see if that solves your problem. The better job we do of sealing out leaks the more likely we are to have a ground problem because the sealers act as an insulator to the flow of electric. Also most of the trailer skin is screwed to wood which when dry doesn't conduct current very well.
Remember; Grease your ball hitch before hitching camper to ball on truck. The fresh grease does many things for you but one of the main things it does is, it helps establish good ground to truck. Also the lights are meant to work while hitch is hooked to tow vehicle. Ground from truck to connector on harness, and also ground from trailer frame to connector on harness. Also clean grounds on individual light assemblies by cleaning the surface the screws touch on back of light assembly plates and then use new screws to connect/install back on camper skin. If new screws don't bite the skin there won't be a ground either. That would need bigger diameter screws or remove light assemblies to "re-ding" the screw holes in camper skin back flat then re-install the light assemblies. Just sayin, 9 times out of ten it is Ground, Ground, Ground! Good Luck.