Trailer wiring problems

[12poundbass]

I rewired my trailer because the old lights and wiring were well past their prime. Got it done, pretty simple and strait forward. Hook it to my truck and nothing. Long story short, I have power going to the lights, I checked and there's continuity at the lights so it isn't the lights. Any ideas? Thanks in advance. 

[J Francho]

Start with a dumb one: check the fuse.

[12poundbass]

I checked the left blinker fuse and it was blown, replaced then we went to checking the power down the line. I didn't look at the other fuses because I assumed if there's 12 volts all the way to the lights the fuses would be good. Can there still be 12v even if there's blown fuses? 

[Log Catcher]

You will have 12 volts to ground through the connectors on the tail light, turn signal, or brake lights. You could possibly have a bad ground connection on the trailer. If you are getting 12 volts at the lights on all you connections you could have bad bulbs. Are these standard lights or LED trailer lights?

[12poundbass]

Standard. I looked at them and they appear to be good. The instructions said the ground was through the lights connecting to the trailer.

 

Let me add this.... I have a round to flat adapter that plugs into my truck. It glows to let you know you have power. When I hook the neutral to the trailer the plug quits glowing. I still have 12v no matter. 

[mattkenzer]

Did you attach the ground wire to the trailer?

Also, are you calling the white wire the neutral?

[Log Catcher]

I have heard of some cases where the hitch ball and coupler on the trailer had to be clean as this was how the ground connection was made.

[12poundbass]

32 minutes ago, mattkenzer said:

Did you attach the ground wire to the trailer?

Also, are you calling the white wire the neutral?

I'm calling the white wire the neutral and that's short and attaches to the trailer. It kinda confused me and I assumed it should be green and the ground. I read in the instructions when we started to trouble shoot that the ground was through the lights attaching to the trailer so that was the other reason I'm assumining the white short wire is the neutral.

[mattkenzer]

The short white wire is your ground.

The brown wire is running lights.

Green and Yellow are the Brakes and Signal.

[12poundbass]

14 minutes ago, mattkenzer said:

The short white wire is your ground.

The brown wire is running lights.

Green and Yellow are the Brakes and Signal.

Ok so the short white wire (that should be green lol) connects to the trailer. When I do connect it to the trailer the light goes out on my adapter plug but I still have 12v to the lights but no lights. Any ideas there? 

[mattkenzer]

When you read 12V at the light, do you have something on? Turn signal, Brake, Light etc.

[12poundbass]

Yes to make it easy I just put my hazards on and check both sides and it's a 'blinking' 12v like it should be. I turn my lights on it's a solid 12v like it should be. 

[mattkenzer]

Hook a piece of wire to the white ground and run it back to the light to ensure it is grounded properly.

If you touch the end of the threaded rod coming out of the light with the ground wire, the light should turn on.

Make sure you have your lights on and the brown wire hooked to the (brown or black on the light).

[J Francho]

Matt's got all the right answers...  thanks!

[12poundbass]

12 minutes ago, mattkenzer said:

Hook a piece of wire to the white ground and run it back to the light to ensure it is grounded properly.

If you touch the end of the threaded rod coming out of the light with the ground wire, the light should turn on.

Make sure you have your lights on and the brown wire hooked to the (brown or black on the light).

My BIL is the wiring guru and we were going to try that but we didn't have enough wire at his house. We ran out of time last week but I grabbed some wire from my house so we can try that when I get out of work. Thanks for the help!! 

[mattkenzer]

1 minute ago, 12poundbass said:

My BIL is the wiring guru and we were going to try that but we didn't have enough wire at his house. We ran out of time last week but I grabbed some wire from my house so we can try that when I get out of work. Thanks for the help!! 

All good .... Keep me posted.

 

[12poundbass]

3 minutes ago, mattkenzer said:

All good .... Keep me posted.

 

Will do. I'm going to pick up shrink tubing on my way home because the other I had was too big. Is trailer lighting wire typically 14ga? 

[mattkenzer]

27 minutes ago, 12poundbass said:

Will do. I'm going to pick up shrink tubing on my way home because the other I had was too big. Is trailer lighting wire typically 14ga? 

Normally 16 gauge i believe.

[Log Catcher]

You may need to clean the areas where the trailers lights are mounted to insure you have a good ground connection.

[Ratherbfishing]

Throw out the trailer and start over.  Kidding (sort of). 

 

USUALLY the problem is a bad ground and that USUALLY is caused by corrosion.  Clean all the connection points thoroughly with a fine wire brush.  Also, what has helped me is to use a pliers and crimp the male ends ever so slightly so they are "out of round" just a hair.  This helps keep contact in the connection points.

[Log Catcher]

I hope you get your wiring straightened out. If you are getting 12 volts at you connections you might want to try this. Take the lens covers off your lights and remove the bulbs. Take your volt meter and check the the voltage inside the sockets. Be careful not to let the leads touch each other doing this. If you don't have voltage the problem is probably in the ground wiring. If you have voltage either the bulbs are bad or something is keeping them from making good contact in the sockets.

[12poundbass]

Thanks everyone! I wish I could say for sure what it was besides gremlins! I get there and we hook the wires up no different then last week and they worked with and without the ground. Solder and shrink tube them button everything up and head home. Park the boat and check the lights and no dice! Head back over and he wiggled the harness from my truck and they come back on. I get home and they aren't working. Hook up the ground and they're working great and brighter than ever! Gremlins! LOL

[slonezp]

You 100% sure it's not the connector on the truck? I know my issue is with the connection between the truck and trailer. A couple weeks ago I bought a new 7 to 5 pin adapter thinking that would resolve my issues. Still having some issues so yesterday I ordered a new 7 pin connector for the truck.

[12poundbass]

7 hours ago, slonezp said:

You 100% sure it's not the connector on the truck? I know my issue is with the connection between the truck and trailer. A couple weeks ago I bought a new 7 to 5 pin adapter thinking that would resolve my issues. Still having some issues so yesterday I ordered a new 7 pin connector for the truck.

I pretty sure it isn't the plug. The wire harness at the hitch was loose and I'm thinking it might need to be replaced. I'm hoping to finally launch this thing this afternoon so we'll see. When I unhooked it last night everything was working great and the lights were plenty bright after connecting the ground so fingers crossed. 

[mattkenzer]

As long as those Gremlins keep you moving forward, it's all good.