I know this topic has been talked about previously... I searched old threads but couldn't really answer my question or solve my problem.
I just attempted to rewire my trailer lights this past weekend. I bought a roll of the 4-wire trailer wire..... brown, green, yellow and white. After reading which wires controlled what I got down on the ground and crawled around for a couple hours on Sunday. I thought I had everything just perfect and plugged it all in and poof..... I had problems.
I connected the brown wire to all my clearance/marker lights as well as the tail lights. I then used the green and yellow to connect to the turn signal wire on my tail lights. The white is grounded to the frame of my trailer.
When I turned on the headlights in my truck the entire left side of my trailer lit up just fine.... it was great.... the problem was that the entire right side of my trailer got nothing..... no lights. I then tested my turn signals and both worked perfectly. Brakes worked perfectly as well.
Here is where my confusion is.... is the brake light signal coming through the brown wire or is the brake light signal coming through the green/yellow 'turn signal' wires?
Also... I'm confused as to why they only supply one brown wire in a standard roll of trailer wiring..... shouldn't there be two.... one for each side? I kept the existing brown wire on the right side of the trailer (the side I have issues with the running lights on) and then ran the new brown wire down the left side.... I spliced them together before the meet the male connecto at the tongue of the trailer. Could I not be getting enough juice to power both sides or could this just be the old crusty wire I have on the right side?
I know this is an enormous post but I've thought this over in my head for 2 days now and can't figure it out.
Does the brake light signal come through the green/yellow wires? That makes more sense to me but I'm not sure.
I appreciate any and all help I can get on this. It's driving me freaking crazy and my whole body is sore from crawling around under that damn trailer all day long.
Brake light circuit shares wiring with turn signals. In operation turn signals will override brake light operation.
Check to see that you haven't severed the running light wire at a point after the last running light that works. Make sure all grounds are OK.
You can get a "Y" harness that splits side to side instead of having to run down one side and part way back on the other.
make sure you have a good ground don't rely on the trailer hitch to ball. Check all the grounds on the trailer to make sure they are making good contact. Also, check your splice to make sure the wires didn't break inside the insulation.
As far as the brakes, yes, they go through the signal circuit wires.
white = ground
brown = tail/running lights
yellow = left brake/signal lights
green = right brake/signal lights
And what Cas said about grounding through the ball. My lights don't always burn properly just sitting there, but move the truck a little & they will be fine.
Hope this helps, wiring can be a pain.....
This definitely helps me. At least I know that I'm only missing one piece now.... some place from the front of the trailer to the back, on the right side... I'm having a bad connection with my brown wire. It makes sense as that is the old crusty wire that I kept on the boat.
Another thing that happened is something shorted and I lost my running lights on the left side of the trailer and the dash lights that light up my tach/spedo in my truck no longer work. I haven't had a chance to check all my fuses in my truck but hopefully that's all it is.
As for wiring being a pain..... you're damn right. I thought it would be a one or two hour project and it turned into this gigantic pain in the ass! lol.
Thanks for the feedback... I really appreciate it!!!
PS...
In regards to the ground....
I have my harness grounded to my truck, and then that white ground wire connects via my 4-round plug to my trailer male 4 round connector. I then have the male connector white ground wire come connected to the tongue of the trailer.
That would be a good ground... yes?
I hope that made sense. I reread it several times now and I'm starting to confuse myself!
If I am reading this right you said you left the old crusty brown wire on the trailer to the side that is not working. If this is the case replace that old wire with new. If you blew a fuse I would be willing to bet that wire is cracked somewhere and grounded out on the trailer frame and blew the fuse. As far as you ground If all other lights work and are not flickering your ground should be fine. My ground is done the same way.
What kind of truck? A buddy of mine was having trailer light problems and was blowing his dash and tail lights out. He has a 2000 silverado and had it wired direct to his vehicle wiring. Chevrolet usually has an extra trail pigtail above the spare tire, so if you blow fuses you truck lighting wont blow as well. I'm not sure what other manufacturers have as far as wiring goes.
PS...
In regards to the ground....
I have my harness grounded to my truck, and then that white ground wire connects via my 4-round plug to my trailer male 4 round connector. I then have the male connector white ground wire come connected to the tongue of the trailer.
That would be a good ground... yes?
Should be. When you first posted, I went outside to check my truck to be sure, before I responded.
My work truck was wired before I bought it, somebody grounded the light plug straight to the bumper, to eliminate any problems grounding through the ball, I would imagine. Does the trick though....
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