Help a guy figure out trailer lights

[SMKR]

O Ok, this shouldn't be this hard, but it has me already scratching my head. Last time I did this with my boat a few years ago I made the mistake of mounting all the lights, then trying to wire everything.

This time all I've done is run 25' of cable along the bed of the trailer, and temporarily hooked it up to my flat four connector which hooks to my truck.

Now, I'm installing LED running lights on the rear of my trailer, in addition to your normal tail lights, it's actually an led light bar. I'd like it to act as a stop/turn in addition to running lights, not sure if it will work that way.

Here is what's stumping me. The four wires are all labeled as you can see. But when I turn on my parking lights only the white wire (labeled ground) lights up with my light tester. Shouldn't the brown wire labeled TAIL LIGHTS be lighting up when I hit it with the tester?

Also, my LED light bar has a green, white and black wire. Which wire connects to which wire of my four off my main set of four wires? Here are some pics, I'd just hook up and test different combinations but I fear shorting something out.



On my clearance lights won't black go to tail and white to ground? Guess this is what I get buying all this for ten bucks from a guy down the street without any instructions.

[EW]

Black should ground on 12V systems like car audio, and accessory lights, etc. YMMV.

[shumpertdavid]

You are getting power showing on the white wire because you don't have a it grounded or not grounded well. DC runs in a circle, you have to have a power source and ground for it to work. If you feed power into a lamp and do not ground it, the ground lead will show voltage when touching your test light or volt meter to the lead and the opposing end of the test equipment to ground. Make sure you have a solid ground on the white wire and then retest. You need the white wire to connect through the trailer connector and have a good clean chassis ground to function. Don't count that you can ground the light on your trailer and the hitch and trailer ball will complete the ground circuit to the tow vehicle.

As far as the led strip, you need to know how it's supposed to be wired, just because it has a black doesn't mean that it's the ground wire. In automotive wiring, black is most always a ground in my experience, with the exception of aftermarket lighting. The polarity of a conventional bulb doesn't matter 2 much on a single filament setup, but LED's are polarity specific, it if doesn't light, try reversing the wires.

[LaserSVT]

shump hit it right on the head.

[Mysticcobrakilla]

If you plan on keeping this trailer for a while, ditch the scotch locks.

[SMKR]

thanks guys, got it.

If you plan on keeping this trailer for a while, ditch the scotch locks.

how come? just spent $40 on those safety cables, is there something better? I had chains previously and they were way too small. I bought this trailer in 1990 for $1200, so I think ill keep it a bit longer

[GrayStangGT]

thanks guys, got it.



how come? just spent $40 on those safety cables, is there something better? I had chains previously and they were way too small. I bought this trailer in 1990 for $1200, so I think ill keep it a bit longer

Pretty sure he is talking about those snap on connectors that cut into the wire. They will fail with time. Do it right with buttsplices and a good set of crimpers or if you really want to do it right use solder and heat shrink.

[JC316]

Black should ground on 12V systems like car audio, and accessory lights, etc. YMMV.

Not on my trailer lights. White is ground. Weirded me right out.

[SC457A]

I really got messed up by the trailer wiring. Who in the hell made black positive? White Ground?.... Yellow/ green/ brown/ blue... easy stuff.

[LaserSVT]

Yeah heat shrink and solider if its gonna see any kind of weather. Butt splice isn't ideal for outside conditions.

[GrayStangGT]

Butt splice isn't ideal for outside conditions.

Not ideal, but with a good crimp it works fine for years and way better then the snap on ones.

[LaserSVT]

Not ideal, but with a good crimp it works fine for years and way better then the snap on ones.

So you are agreeing with me agreeing with you?

[line-em-up]

Yeah heat shrink and solider if its gonna see any kind of weather. Butt splice isn't ideal for outside conditions.

I agree. The simplicity of a crimped or twisted connection becomes a pain in the ass to troubleshoot after the wire corrodes at the connection and you have an intermittent or weak connection a few years down the road.

[GrayStangGT]

So you are agreeing with me agreeing with you?

Possibly My point was a lot of people end up with issues due to using shitty crimpers, it is worth it to get some kleins or something similar that will do a good dimple crimp if you aren't going solder.

Or get heat shrink butt splices
[ame]http://www.amazon.com/3M-Heat-Shrink-Connector-Piece/dp/B008HMHJDO[/ame]

[Sean88gt]

Scotch clips are dogshit. You can generally tell the quality of work by that step right there.

Got but connectors with heat shrink and do it like you want it to last.