Righting past wrongs

[Poopdeck 0]

I have two boat trailers and a cargo trailer. For years I've spent to much time keeping my lights working correctly. Most problems were with the cargo trailer since it is a dump model so the ground has to go through the rusty hinge points. At one time added a second ground to the top of the trailer but this trailer continued to give me fits that only a weak ground can.

 

I'm in the process of a major kitchen rip out and my trailer lights were causing more frustration then ripping out the entire kitchen, dining room, soffits and walls. So I ripped out all the trailerwiring and lights and replaced them with LED lights with each light having a dedicated ground to the tow vehicle. I should have done this ten years ago. What the hell was I waiting for. This should permently solve any further trailer light issues. Next up, after the kitchen, boat trailers!

[Dave G. 0]

LED lighting is awesome, before I retired we were outfitting the larger commercial vehicles with it. LED lighting uses way less energy, they run cool,less prone to internal breakage from vibration and last seemingly forever, you're doing a good thing congrats !

[Poopdeck 0]

The ground to the tow vehicle is the money shot. Grounding to the trailer is just plain stupid and it escapes me why this is the norm and why I've done it that way my entire life. About the only thing I can think of is grounding to the trailer saves about 8 dollars in wire and a couple minutes of labor.

[flyty1 0]

A tip for anyone who backs their trailer in the water to launch (especially in salt water). Unplug your trailer lights before you get the lights wet - avoiding driving the corrosive galvanic reaction that will cause them to fail.

[mikechell 0]

Just a few comments on this:

1) Grounding to the trailer or the frame is normal procedure because we've been doing it on automobiles forever. With a little maintenance, it's a viable option for common ground systems. It's the lack of maintenance, not the common grounding, that's the problem.

2) If you have truly submersible trailer lights, there is no need to unplug them.

3) "Galvanic corrosion" is also called "electrolysis" or "bi-metal corrosion". This type of corrosion only happens while the metals are submersed or still wet. Once dry, the corrosion will be oxidation, not electrolysis.

 

The above points are just observations and opinions. I, personally, run a ground wire for each light to the electrical plug. But I do that because I KNOW I won't maintain the open connections like I should.

[Lesg 0]

I've never met anyone who maintains ground connections until the lights won't work. lol

 

Les

[Dave G. 0]

Also a properly wired conventional system should have a ground running through the connector socket to the tow vehicle anyway. though the frame is common ground, true, still a lot of people rely on the ball socket connection to the tow vehicle to carry the ground. Big mistake.

[Poopdeck 0]

All of my trailers, a 1991, 1993 and a 1997, are all maintained to a fault. Why? Because you have to to ensure the lights work properly when using the frame as the common ground. Most every problem I've experienced with trailer lighting is in the ground. Typically it's a weak ground not a missing ground. So I agree with Mike, the dedicated ground to the tow vehicle (wire plug from the truck) will eliminate almost all light maintenance.

 

I have to disagree with Dave G (sorry Dave) in that that grounding directly to the plug and the lights is not conventionally done. In fact if you don't do it yourself your boat trailer will always use the frame as the common ground. That's the conventional way to wire a trailer and it's considered proper. It's just not the best way to do it. The better way is to run a ground wire from the trailer plug down both sides and directly to the ground of the light. Man I can't wait to do it to my other trailers.

[Bryon Anderson 0]

I know next to nothing about electricity or how it works. I know that I should learn all that stuff, and vigilantly maintain the crappy lights on my cheap Harbor Freight trailer, but honestly, I don't have the time or the inclination to do that at this point in my life. If I'm willing to spend the money, does it make me a bad person if I want to just say "screw it" and default to something like this as a solution?

https://www.amazon.com/Blazer-C6304-Round-Wireless-Towing/dp/B00BJEICDS/ref=sr_1_1?ie=UTF8&qid=1496272792&sr=8-1&keywords=blazer+wireless+round+towing+light+kit

[Poopdeck 0]

Yes it does! I'm a bit anal with trailer lights and find it very unsettling when each and every light does not function properly. LED lights with wiring harness can be bought for 40 bucks at any home center. 50 feet of 14 or 16 ga. White wire is 8 bucks. 3 ft. of plastic split tube is $2.50. Although not necessary, I like to encase in split tube wrapped with electrical tape the exposed wiring from the plug to where it enters the frame and where it exits the frame to the fixture. It just looks more finished and adds a bit of protection to prevent wiring chaffing. So for half the cost of those lights and an hour of your time you can replace your lights and have them work properly all the time with no maintenance ever again until the LEDS burn out.

[Bryon Anderson 0]

I hear you Poopdeck, and in theory I agree with you. However, I've already ripped out all the wiring that came with that HF trailer once and replaced it all with new, including the plugs for the vehicle end and the trailer end. I also encased all of the wiring in split tube from stem-to-stern as you suggested. That worked for all of one trip before the some of the lights stopped working again, so back to the internet I went, and learned that it was probably a problem with grounding. Lots of people suggested running a dedicated ground wire from a bare metal spot on the trailer to each of the trailer lights. I did this for the rear lights (not the side markers), and that, too, worked for one trip. Now, if I understand what I'm reading in this thread (and there's no guarantee that I do), it sounds like this "fix" might have failed because I was still relying on the ball joint connection between the vehicle and the trailer to carry the ground, which is noted to be a "big mistake". So now I need to run those dedicated grounds from each light directly to the plug on the two vehicle, is that right? I'd be willing to give it a try, but I don't even know how I would do that. Do I attach the ground wires just to the metal bracket where the tow vehicle plug is mounted, or somehow to the plug itself? If the latter, where?

 

Oh, I forgot to mention that when I replaced all the wiring, the wiring I used came as part of a full set of lights, so I've replace all the lights, too, albeit with the same filament-type bulbs, not LEDs.

 

Sorry, final "edit" -- I would be willing to spring for a whole new set of LED iights and start from scratch, as I was prepared to spend twice as much for the wireless set.

[mikechell 0]

Just to put everyone's wiring ideas to paper.

 

[Poopdeck 0]

You know earlier today I took the time to write easy to follow instructions on how to ground to the tow vehicle and I guess I forgot to hit post since I don't see it.

 

A picture is worth a thousand words and mikes diagram shows it better then I explained it. Put simply, instead of taking that two foot length of white wire that comes out the trailer plug and bolting/screwing the end to the trailer attach two lengths of white wire to it. Run one white wire down each side of the trailer along with the other wires. Attach the end of the white wire to the white wire coming out of the light. Doing it this way means your ground goes from the negative battery terminal in the tow vehicle, through the trailer plug and all the way back to the trailer lights just like the hot wire starts at the positive battery terminal and goes all the way to the light. 99% of trailer light problems are caused by the ground. The other 1% is the bulb. Most ground problems are caused by a weak ground which you get when your using a painted or rusted trailer frame or the hitch ball as the ground. The hitch ball should never be used for ground.

 

If there is no white wire coming out of the light then the light is grounded through the lights mounting bolt. In this case attach the white wire to the lights mounting bolt. All of the LED lights I've seen have a white and black wire coming out the back.

[Bryon Anderson 0]

Thank you Mikechell and Poopdeck -- I think I might finally understand now. I think I am going to go for the LED lights and run a length of ground wire from each light to the ground wire coming out of the trailer plug as you suggest.

 

I also took a look at the ground wire coming out of the tow vehicle plug today -- it doesn't look like it's attached directly to the vehicle frame, and I keep reading on various websites that it should be. I'm thinking I should find a good bare-metal spot on the car's frame and firmly attach that ground wire there with a sheet metal screw or something. Does that sound right to you?

 

Thanks again for the help guys--I think you're going to end up saving me a bunch of money and frustration.

[mikechell 0]

It's funny, this thread, and then last weekend, I just rewired my trailer.

If you don't "know" or have the equipment to solder and heat shrink the connections, then buy some butt connectors with the sealing gel inside. That will protect the last "weak link" in the wiring.

And yes, the white wire on the vehicle side needs to be connected to a ground. You can "create" a grounding point with a self tapping screw, but if you look around, there might be an existing bolt or screw you can connect to.