Need help, boat wiring

[Texas Proud]

OK, I know there are people who know enough to help me...


I have been having problems with the tail lights on my boat trailer. It started on the right side after we had a blowout... took it in to get fixed because DW did not want me working on it... paid over $100 to get it 'fixed'....

Then, it started on the left side... where the turn signal would not work, but the brake light would...


Today I started to work on it.... took off the left side to see if there was anything wrong... it looked good... bulb looked good...

So, since it was real easy to get the light off, I took off the right side... and found that the insides were rusted badly... took the bulb to the left side and the left side worked... (or so I thought).....

Went to buy a new right side light... hooked it up and the turn signal works, but you can barely see it... parking lights and brake lights do not work.... well, guess what, they do not work on the left side either!!!

Since I had bare wires on the right, I measured the volts.... for the turn signal, I am only getting about 7... for the brake and park lights only 4

I can not see any problem with the little bit of wire that I can see... the only thing that concerns me is that my ground looks like it is in bad shape. However, it is riveted to the trailer and not bolted, so I do not want to cut it because I am then screwed....

Any suggestions

 

[Dimsumkid]

I would use a rust remover. I've used CLR before with good results. Sand off whatever you can get to, use CLR and let it sit for a few minutes and dry it off. Then cover with a light coating of petroleum jelly or WD40.

 

[NW-Bound]

Brake lights use a lot more current because they need to be brighter than turn signals. I do not know about boats, but have a flat-bed trailer and found that its wiring used smaller gauge wires than what I would put in. Cheap bastards.

If your lights were OK before and turned weak now, I suspect that corrosion may have weaken the wires further. You may also have poor contacts in the connector that plugs the trailer into your truck. I would check all contacts, and also the grounding wire that attaches to the trailer frame.

In the worst case, it would not be too tough to get new wires and connectors and to rewire the whole thing. Check out etrailer dot com. I have bought from them.

PS. Just now see your note about the ground point. Oh yeah, that's where the currents from all the bulbs converge. Fix that first. I would drill a new hole in the frame, then bolt a new eyelet for the ground point. Or drill out the rivet.

 

[Texas Proud]

Brake lights use a lot more current because they need to be brighter than turn signals. I do not know about boats, but have a flat-bed trailer and found that its wiring used smaller gauge wires than what I would put in. Cheap bastards.

If your lights were OK before and turned weak now, I suspect that corrosion may have weaken the wires further. You may also have poor contacts in the connector that plugs the trailer into your truck. I would check all contacts, and also the grounding wire that attaches to the trailer frame.

In the worst case, it would not be too tough to get new wires and connectors and to rewire the whole thing. Check out etrailer dot com. I have bought from them.

PS. Just now see your note about the ground point. Oh yeah, that's where the currents from all the bulbs converge. Fix that first. I would drill a new hole in the frame, then bolt a new eyelet for the ground point. Or drill out the rivet.

Thanks for the info.... I have checked and the two wires that I can see seemed to be oxidized (or whatever you call it)... the wires are more brown, not copper colored...

I have been charging up my drill battery... I am going to have to drill a new hole even if I rewire the thing, so I am going to try that first...

Thanks for the website.... I see an LED kit for $55 which is cheaper than what I have found previously... or go with regular for about $35...

 

[NW-Bound]

You are welcome. I did not think or know about the LED lights until you mentioned it. These would be very worthwhile if you are to replace the lights. LEDs would draw easily less than 1/3 the current for the same brightness, hence allow the use of smaller wire size. The total cost may just come out the same.

Additionally, I have read that because LEDs turn on instantly instead slowly brighten up like incandescent bulbs, they are safer due to the fractional second they add to the reaction time of the driver behind you.

This reminds me that I need to work on the lights of my flatbed trailer too. They are always too dim since day one, and I am afraid I may get rear-ended by these stupid tail gaters.

 

[Texas Proud]

Well, put in a second ground wire and it did nothing....

But was looking at a video on the site you gave me and a thought came to me... was I getting a good ground at the light Well, I checked and NO...

It is too late for me to finish today, but I think I found the problem... I have to see if I can get a better ground somehow at the light... just putting them on the bolt did not work for one.... it would come on and then go off.... the other one I just moved the ground around until I found a place it would light... SOOO, let's hope this is it and I can get this behind me...


Still might go for the LEDs.... but at least DW will not be yelling at me about not being able to go boating (that is if it works)....

 

[samclem]

Congrats on the troubleshooting.

Still might go for the LEDs.... but at least DW will not be yelling at me about not being able to go boating (that is if it works)....

Here's a set of LED submersible trailer lights from Harbor Freight for $40. I don't know about the quality, but maybe they'll sell you the extended warranty for a few bucks if you are interested.

 

[Texas Proud]

Congrats on the troubleshooting.


Here's a set of LED submersible trailer lights from Harbor Freight for $40. I don't know about the quality, but maybe they'll sell you the extended warranty for a few bucks if you are interested.

Thanks for the link, looks like a better deal. I will see if I did find the problem or not tomorrow... crossing my finger...


Edit to add.... I was looking at them a bit more... these are submersible, not waterproof.... but with an LED I guess it does not make a difference... probably only the fittings... add some more.... the others were submersible... I thought I saw some waterproof...

 

[pb4uski]

On my boat trailer IIRC, the trailer needs to be on the hitch for the ground to work properly - not sure if this testing you are doing is with the trailer on the hitch or with the tow vehicle just backed up to the trailer.

Sometimes it is easier to just rewire and replace the lights, particularly with the issues that you have been having of corroded wires et al.

P.S. Not sure what you do but I usually unplug the trailer when the lights will be submersed - a fried swears that it makes a difference but it seems to me that it can;t hurt. Every once in a while DW will forget and I'll see the brake lights under water as I am driving the boat onto the trailer.

 

[Texas Proud]

On my boat trailer IIRC, the trailer needs to be on the hitch for the ground to work properly - not sure if this testing you are doing is with the trailer on the hitch or with the tow vehicle just backed up to the trailer.

Sometimes it is easier to just rewire and replace the lights, particularly with the issues that you have been having of corroded wires et al.

P.S. Not sure what you do but I usually unplug the trailer when the lights will be submersed - a fried swears that it makes a difference but it seems to me that it can;t hurt. Every once in a while DW will forget and I'll see the brake lights under water as I am driving the boat onto the trailer.

Boat is hooked up to tow vehicle... and I can see where it would make a difference...

So far we have not forgotten to disconnect the wires.... I also do not reattach them until the boat is on the trailer and out of the water.... so my DW can not do what yours does.... unless of course she decided to attach them herself....

 

[Lazarus]

Do you have a four wire trailer connector? If so the white is usually the ground. The ground must work all the way through to the tow vehicle.

Trailer Wiring Diagrams | etrailer.com

If you have to have the trailer on the ball to work then the wiring is not correct or defective. The ground on the tow vehicle plug must be connected to chassis ground on the tow vehicle. If it works on the ball then the fault is with the tow vehicle ground connection.

The trailer lights themselves are usually grounded to the trailer frame at their mount point. There will be a ground wire from the plug to the trailer frame, which is what you are probably talking about.

Get a multimeter so you can measure voltage. No need to guess what is happening. They are cheap and handy.

 

[painterbill]

Corrosion is normally 99% of the problem with trailer lights. Most small boat trailers use a 4 wire flat or round plug with one wire for running lights, one for left brake/turn light, one for right brake/turn and one for a ground wire. When one light, brake or turn, does not work I would look at that individual wire or bulb element. When the lights are weak or not working as designed I would look at the ground wire, both at where it attaches to the trailer and where it attaches to the tow vehicle. Normally on the trailer the ground wire is attached to the trailer frame close to the hitch coupler, I would attach a new wire terminal to the wire, clean the frame and reattach. I would then do the same to the ground wire on the tow vehicle, new terminal end and clean tow vehicle frame and reattach. In a perfect world, you should be able to hook the trailer wiring harness to the tow vehicle without hitching the trailer and all lights work properly because all lights are grounded through the wiring harness to the tow vehicle. If the lights only work (or are brighter) when hitched then the grounding system is failing and the trailer lights are grounding through the hitch ball.

As far as unplugging when launching the boat it is a good idea to unhook the wiring harness before backing into the water. Because when backing in to the water you are using the brakes which will cause the brake light bulb(at least incandescent bulbs) to be hot and when the hot bulb hits the cold water it can cause the bulb to crack or break.

 

[youbet]

If you have to have the trailer on the ball to work then the wiring is not correct or defective.

Yep, gnd is supplied from the tow vehicle through the electrical connector independently from the hitch's mechanical connection. There's an issue if the trailer and tow vehicle need frame to frame contact for the trailer electrical system to work.

As far as intermittent operation of the trailer lights, because the sockets and connections get submerged and you've observed rust and oxidation, it's time to replace them. The easiest way is probably to purchase complete assemblies. Otherwise, you'll be chasing intermittents forever.

 

[NW-Bound]

+1 on the proper ground wire voiding the need for frame-to-frame metal contact.

The OP does have a meter. But when the wires and metal parts become so corroded that one does not have a clean shiny metal surface to apply the probes to, it's time to toss them all and start over.

I do not have a boat, but can imagine the problem that boaters have. When submerged, any part of the wiring or the light assemblies that is exposed and getting wet becomes electrodes if power is applied. That speeds up corrosion of the anodic parts, and the electrolysis also causes calcium and other mineral gunk to get plated on the cathode.

The other day, when contemplating lubing the bearings of my flatbed trailer, it occurred to me that boaters must check theirs a lot more frequently than I do mine.

 

[pb4uski]

.....the other day, when contemplating lubing the bearings of my flatbed trailer, it occurred to me that boaters [-]must[/-] should check theirs a lot more frequently than i do mine.

fify

 

[NW-Bound]

Talk about trailer wheel bearings, a friend of mine told me a story about how his uncle lost his travel trailer. Its bearings got hot, and set the tires on fire. When he discovered it, all he could do was to stop by the side of the road and watch the entire TT engulfed in flame.

 

[REWahoo]

Talk about trailer wheel bearings, a friend of mine told me a story about how his uncle lost his travel trailer. Its bearings got hot, and set the tires on fire.

That is why I have one of these and shoot my wheels with it whenever I stop for a break: Amazon.com: HDE Temperature Gun Infrared Thermometer w/ Laser Sight

 

[NW-Bound]

Yet, people do not have to check car wheel bearings like that. What's wrong with these trailer bearings?

Anyway, boat trailer bearings get submerged, and that would greatly increase the risks of failure.

 

[REWahoo]

Good question. My only guess is sealed bearings might be cost prohibitive, but even high-end trailers don't have them (at least I don't think they do) so maybe not.

 

[Texas Proud]

Thanks for the input...

I had to grind off the paint to get good contact on the ground... almost all lights are working and are bright...

My one remaining problem is the right brake light.... no matter what I do, it will not work...

I had problems with the turn signal, but ground the trailer a bit more and got good contact and the turn signal is nice and bright.... decided to change the bulb to see if that made a difference.... nope...

SOOO, will order the LEDs and use what I have for the time being... if the LEDs work without rewiring, great... if not, then I have some work to do since I have side lights and am not sure how I am going to fish the wire out of the frame... I have a tube frame the whole length of the trailer...


PS... I did not check the volts on the brakes after doing this... but I do not want to attempt the rewiring right now so it really does not matter...

 

[painterbill]

If your trailer is a 4 wire plug and the right turn signal works then the right brake light should work. It still sounds like you may still need to work on the ground or after driving ]while it may pick up some ground through the hitch.

 

[Texas Proud]

If your trailer is a 4 wire plug and the right turn signal works then the right brake light should work. It still sounds like you may still need to work on the ground or after driving ]while it may pick up some ground through the hitch.

It actually is a 5 wire, but I do not know what the 5th wire is for since I do not have brakes or a reverse light... I am using a 4 wire to connect to the tow vehicle...

The funny thing is that the light WAS working... I took it off to check the bulb on the left since I knew that bulb was working and saw that it was WAY rusted out.... the left was not working, but it was only the bulb...

I still want to work on the ground close to the plug... I added a second wire but have not got it as tight as it needs... I am using a wood screw on the metal...

I agree... I do NOT know why it is not working... it should be.... and the ground seems to be good as the light became a lot brighter on the turn signal the last time I put it back together....

Edit to add... it is on the hitch... I have not taken it off while doing the work....

 

[sailor]

That is why I have one of these and shoot my wheels with it whenever I stop for a break: Amazon.com: HDE Temperature Gun Infrared Thermometer w/ Laser Sight

Do you need this level of precision? Do they heat up so much?
Or you just don't like to touch them?
I use low tech method and check my boat trailer bearing by touching them - so far they have been warm and not burning hot I and hope they stay this way

 

[REWahoo]

I use low tech method and check my boat trailer bearing by touching them - so far they have been warm and not burning hot I and hope they stay this way

I'm all for old school as long as I don't have to show up for class.

It's that "burning hot" part I want to avoid touching, thus the (birthday gift) IR gun.

Slightly off topic, but I found it a neat [-]toy[/-] tool to check for insulation leaks around the house. I shot all my ceilings and discovered missing attic insulation in one area that has always been difficult to cool in the summer.

 

[NW-Bound]

The above application is a very worthwhile use. I did not know these IR thermometers have that good a sensitivity and resolution. I am ordering one now.