Submersible lights for boat trailer
 

After submerging submersible lights on trailer yesterday, they are acting funny
Left signal ( drivers side) works good, break lights work good, right signal turns both ( left and right) signals on and only one light ( left) turns on when I turn lights on :angry3:
Do I need to re wire everything or just change lights ?
And which ones are good ones?:thinking-006:
Thanks

Don't think trouble shoot it, check wiring if it was good before likely something minor
get out the test light

Check for corrosion at the connector or the ground.

Do you have the crappy 4 way flat connector for your trailer wiring?

I've found those are terrible for corroding in the tail light terminal of the truck side over the winter. The salt eats them since it's energized whenever the truck lights are on. Some dielectric grease helps a bit. (Preventive not a fix)

Like Dutchpirate said a poor ground is at least one of your issues. (The signal light)

If you unplug your lights when launching you don't need submersible lights.

What do you mean by test lights :thinking-006:
How do I find that something minor?

Yes 4 way flat connector

You're in trouble, have you got a handy friend?

He means a test light which is used to check powers and grounds in a circuit. It has a bulb in it with a probe on one end and an alligator clip on the other. Put the clip on a ground and check for power or put the clip on a power and check grounds.

A properly wired 4 way is like this.
White- ground
Yellow- left
Green-right
Brown-tails

I thought it was
White -power Green - ground. I wired my neighbors trailer yesterday and hooked it up that way. I did just match colours, and put in a new ground wire screw, everything works perfectly now.

An easy way to remember the left and right is. Yellow has an L in it and Green has the R. The white terminal is bare coming off the truck so you don't want power on that one.

You can wire it however you want as long as it works but you can run into trouble towing different trailers.

Ok, thanks. The trailer light my neighbor had were very dim. We changed the ground screw and sanded off the rust but that didn't help. Then checked the feed from the van, the white wire was not connected, I connected it to the white going into the trailer and everything works proper now ! Is this going to cause an electrical problem ? :scared0015:

Sounds like you got it right if I understood you. By having a ground screw only on the trailer your relying on a good ground being available through the ball. This is why you sometimes see lights flickering and going out when the tow vehicle goes over bumps. A ground wire from the tow vehicle is best. It sounds like this is what you did by connecting the white wire out of the van to the trailer wiring. If you screw up the powers and ground you'll blow fuses so I'm thinking you're ok.

Makes sense, thanks again !:)

Amateur hunter a simple thing to do would be to remove the lense on the right hand light and see if there's anything obvious going on in there.

Your brake lights and signal lights use the same wire and bulb filament so we might be safe to assume the wires for those to that light are ok.

We don't know if the wire is good for the tail light circuit.

Inspect the light bulb for being broken (they shatter if you put hot bulbs in water) I'm doubting it since the signal still works.

Inspect the bulb and make sure both filaments are good and they are not touching each other.

Inspect the ground off that bulb socket. The bulb grounds through the outer metal part of the socket if it's rusty it may not get a good ground. Sometimes there is a ground on the mounting plate. It's possible (even likely) there's no ground at all and it's using the trailer frame.

If you look into the bulb socket you'll see two lead terminals, that's where the power comes into the socket. The plate those terminals are in must be able to slide a bit in the socket to maintain tension on the bulb terminals.

There's a few things to look at without knowing precisely how it's wired.

A test light is a handy tool and easy to use. Well worth the 20 bucks if you're going to be pulling trailers. Trailer wiring can be a never ending battle it seems. Most factory wiring jobs are very poor.

I have one of these testers to make sure my vehicle is sending through the plug. Very handy for trouble shooting when you can easily tell if your vehicle wiring is part of the problem. I got mine at CT, but I'm sure they're readily available.

Thanks man
Where can I buy that tester?

Pm sent

Problem solved
 

Ground connection was rusty, cleaned it, add electrical grease , reconnected and all works fine :sHa_shakeshout:

Thanks all for your help

:sHa_shakeshout: