trailer wiring

[pkrainert]

Hey guys,

I just rewired my trailer and when i turn on the turn signal both lights go off like the hazards are on. I have traced the wires numerous times and its all hooked up correctly. If I hook up one side at a time they work perfectly but when they are both hooked up they dont. Could this be caused by a bad ground?

 

[pkrainert]

Re: trailer wiring

By the way I am using a 4 flat from the truck which i tested and is working.

 

[Proselect]

Re: trailer wiring

Just to make sure, you have the white to ground, the brown to the running lights, and the green and yellow to the turn signals? If it is all hooked up correctly then I would suspect you have a problem in one of the back llights where its back feeding through the running lights somehow and causing both sides to go at the same time. Could be as simple as a shorted bulb filiment.

 

[pkrainert]

Re: trailer wiring

yep white is going directly to the trailer with a metal screw, brown to both running lights and yellow for left turn and green for right turn... i will take the lights apart when i get home.

 

[captharv]

Re: trailer wiring

Take a battery jumper cable from the trailer frame to the car frame. If it works right then, bad ground.
How did you attach the grounds at the lights themselves? On my trailer I had to use the dremel to shine them up to get the lights working right. Then, I coated the connections.

 

[kenmyfam]

Re: trailer wiring

3 Top Reasons for trailer light issues

#1. Bad Ground
#2. Bad ground
#3. Bad ground

That is if the wires are in the correct place to begin with.

 

[199675hpforce]

Re: trailer wiring

I just re did two of my boats both being 17s. Dont use old lights and housings even 2000 or older its not worth the effort. I went to Cal Ranch store picked up new side markers four of them and redrilled my trailer. Also bought light kit from Walmart $28 with new wiring. Heck i even used Cal Ranch farmers paint in white plus primer to hit the whole trailer after scuffing it good. Now for the wiring go ahead and pickup couple packs scotch locks,bullet connectors,heat tape or the new brush one type at walley world. Run a new ground wiring down each side with extra length, connect this to same wires that ground onto each light. Converge the two whites running down the frame into one and connect to wiring harness up front scotch it,use dremel and clean up a good ground for white wire at harness. Get lots 3/4 new stainless bolts if you can 1/4inch with locks, also going to need some size 10's bolts with nuts. With scotch locks your connecting and ground twice! My trailer lights work great even when not hooked up to my truck. Also check your trucks ground my nissan bed has no ground lol? Figured this out light would work when connected but not when the ball wasnt attached. Placed this in frame and now im good to go. Brown is for park lights, yellow and green for signals and brake im not sure think brown. Get some $2.99 mainstay wally world 100 percent silicon clear caulk get this stuff anywhere a wire could rub plus hit all the connection areas it might make it water tight. Hit the side markers real good to keep out water. Both trailers work great now i opted not to replace side markers on one boat because it was fairly new but found quickly they had connection issues inside the housing. Always just replace these suckers.

 

[Knightgang]

Re: trailer wiring

If you do as 199675hpforce suggests and split the white ground sire into two leads and run them down the length of the trailer to the lights, then you will not need to attach the white ground to the trailer. The reason for attaching the white ground to the trailer is because most wiring jobs use the trailer frame as the ground at the lights, so you have to pick that ground up at the tounge to complete the eletrical ground circuit with the tow vehicle. If you run the ground all the way to the lights, then you have not passed that ground through the trailer frame, thus no need to connect ground to trailer tounge.

Personally, due to problems with corrosion on ground connections and such, next time I rewire one, I will run the ground wire all the way to the lights. IMHO, that is the best and sure way wire the lights...

 

[199675hpforce]

Re: trailer wiring

I did go ahead and ground to trailer as well. Double ground lol. Wonder why manufacters dont do this? Even if one ground wire gets cut light still works. The idea of finding a bad ground using jumper cables is a good one but only on older vehciles. New cars use ECMs computers that could be damaged and very expensive to replace.