Trailier Light Wiring - driving me nuts!

wifisher

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Re: Trailer Light Wiring - driving me nuts!

Re: Trailer Light Wiring - driving me nuts!

So...lets see. You have two lights at the back of the trailer. Marker lights at the center. 4 clearance lights on the side. A license plate light. You actually run 8 seperate ground wires? I will pass on that. I am an electrical engineer. I think I can figure out what is less complicated.

It has nothing to do with being an electrical engineer. The fact is that on some trailers, there are problems with frame grounds. Obviously, you have not owned or repaired any of them. That does not mean that they do not exist. Think about a painted tilt trailer. If you are an electrical engineer, you should be able to see the potential for problems grounding to the frame.
 

bruceb58

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Re: Trailer Light Wiring - driving me nuts!

Re: Trailer Light Wiring - driving me nuts!

A tilting trailer has its own issues. A tilting trailer is a rare breed these days but where they exist, you use a grounding strap between the two sections. If you have a one piece welded frame, there is absolutely no need to run seperate grounds to each light.

I currently own 4 various types of trailers ranging from utility trailers, boat trailers and horse trailers. I have owned numerous more in my lifetime. I never have a problem with lights.

Obviously, you have not owned or repaired any of them.
This is obvious how? The only thing that is obvious is that I know how to correctly install and maintain my equipment. You think I am just lucky that I have never had a problem?
 

rbh

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Re: Trailer Light Wiring - driving me nuts!

Re: Trailer Light Wiring - driving me nuts!

Just a thought, if your trailers frame is "all welded together" (not bolted) frame will be a good ground for all lights and brakes ETC

Remember your grounding point must be to the frame, not the hitch if it is a bolt on type (super high resistance)

Get a welder to weld on a good grounding lug to attach to.
 

smokeonthewater

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Re: Trailer Light Wiring - driving me nuts!

Re: Trailer Light Wiring - driving me nuts!

Fact is there is nothing at all wrong with a floating ground. Both methods have advantages... the biggest advantage of grounding through the frame is simplicity. Some trailers have multiple bolted together joints and or movable parts and a frame ground on those often requires several ground straps to act as jumpers between parts. Those can be trouble.


I personally prefer the use the chassis ground but it really isn't fair to fault someone for running a floating ground.

Another neat little trick I use is that my clearance lights are not spliced into my tail light wires all through the trailer. Instead I make one splice at the front of the trailer OR use a junction box and run a single wire down one side, across the back and back up the other side to power the clearance and ID lights..... It is a little more work but it has two advantages... one is separating into two systems for trouble shooting and the other is protecting the tail lights from failing (and possible causing an accident if one of the many splices in the clearance lights fails.

BTW I use all high quality fully sealed led's .... totally worth it in the long run
 

bruceb58

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Re: Trailer Light Wiring - driving me nuts!

Re: Trailer Light Wiring - driving me nuts!

Fact is there is nothing at all wrong with a floating ground.
I think you and I have different definitions of what a floating ground is. You mean single point ground?

Sealed lights here as well. Replacing with LEDs as they fail.
 

smokeonthewater

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Re: Trailer Light Wiring - driving me nuts!

Re: Trailer Light Wiring - driving me nuts!

That IS possible.... by floating ground I mean that the (-) wires are run to the (-) or white wire of the trailer plug and do not rely on the frame of the trailer to carry any current..... Obviously the trailer is not totally insulated from the grounded chassis of the vehicle because of the trailer hitch tho.

I described two different situations in my last post.... One that was sympathetic with the other poster and mine which is grounded the same way as yours.
 

mike64

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Re: Trailer Light Wiring - driving me nuts!

Re: Trailer Light Wiring - driving me nuts!

Fact is there is nothing at all wrong with a floating ground. Both methods have advantages... the biggest advantage of grounding through the frame is simplicity. Some trailers have multiple bolted together joints and or movable parts and a frame ground on those often requires several ground straps to act as jumpers between parts. Those can be trouble.


I personally prefer the use the chassis ground but it really isn't fair to fault someone for running a floating ground.

I agree with Smoke. I really don't understand why anyone would have a strong opinion either way, even an electrical engineer- the best way to ground a trailer is the way that works. If it grounds through the frame, great. If I took ownership of a trailer that grounded through the frame and the lights worked fine, I wouldn't add ground wires. But, as said, if you have a trailer with multiple parts and maybe some corrosion issues, what's easier- doing painstaking continuity tests to figure out where the ground is failing and adding grounding straps to the frame, or just running a little ole ground wire?
 

bruceb58

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Re: Trailer Light Wiring - driving me nuts!

Re: Trailer Light Wiring - driving me nuts!

I subscribe to the KISS principle. You can Rube Goldberg up anything you want on your own trailer but advising the OP to do the same is not responsible and will put him through a lot of unnecessary work and expense.

If the trailer came from the factory without seperate ground wires, none should be added.

In the OP's case, none of his lights are working which points to the basic ground between the vehicle and the trailer itself. That is where he needs to start. He can attach a jumper cable from the frame of his vehicle to the frame of the trailer to diagnose that connection. If none of his lights work right now, running individual wires to each light won't solve his problem if the issue is the vehicle/trailer ground connection.
 

Thalasso

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Re: Trailer Light Wiring - driving me nuts!

Re: Trailer Light Wiring - driving me nuts!

Take a wire and ground it direct from the trailer and to bumper of trk. see if it works then. I know some trailers need to have good contact from coupler to the ball.
 

Thalasso

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Re: Trailer Light Wiring - driving me nuts!

Re: Trailer Light Wiring - driving me nuts!

Take a wire and ground it direct from the trailer and to bumper of trk. see if it works then. I know some trailers need to have good contact from coupler to the ball.
Make sure your trailer is plugged into the trk wiring plugh.
 

bruceb58

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Re: Trailer Light Wiring - driving me nuts!

Re: Trailer Light Wiring - driving me nuts!

You never rely on the ground through the hitch. That is why there is supposed to be a ground that runs through the trailer connector.
 

mike64

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Re: Trailer Light Wiring - driving me nuts!

Re: Trailer Light Wiring - driving me nuts!

I subscribe to the KISS principle.

My point was, sometimes it is simpler to run a ground wire than to try to figure out why the frame isn't grounding. And I wasn't advising the OP in the first place, I was responding to someone else's question about how you do it. I agree with you that in the ideal situation, with a shiny new trailer out of the factory, you shouldn't need ground wires. But I think there are valid circumstances to do so. You obviously feel very strongly that this should never be the case, and I'm not going to convince you otherwise, nor do I want to. We're just rehashing our points now, so I think we will just have to respectfully disagree.
 
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