# Trailer light problems



## BigTerp (Nov 17, 2013)

Took my boat out yesterday morning to do some waterfowl hunting. Did my usual trailer inspection before leaving the driveway and noticed my turn signals weren't working on the trailer. All the trailer lights were on, but wouldn't flash when the turn signal was on. I tried my four ways as well with no luck. They also wouldn't "brighten"when I applied the brakes. So I unhooked the wiring harness and reconnected. Now the left taillight stopped working completely. Today I tried to pull the bulb and shattered it. Not sure if it was bad or not, but it certainly is now. It seems stuck. I tried the right taillight and it seems really tough to remove also. Didn't want to break that one as well so I left it alone. So, I need to figure out how to replace the busted bulb and what would have caused the trailer lights to be on but not function when braking or engaging the turn signal. My rear lights are Peterson dot aist 90 440. Any help is greatly appreciated!!!


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## TNtroller (Nov 18, 2013)

Sounds like the connectors are corroded/rusty since you had trouble removing any bulbs and the lights work but not correctly, also may have a bad ground somewhere. If both rear lights are acting up, I would just replace both light fixtures, each side is only $10-15 vs the hours you could spend trying to fix 'em or track down the issue. New wiring is a possibility, not hard to do but another $20 or so for the new wiring harness. Use some electrical grease on all the connectors and bulbs to avoid this again.


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## BigTerp (Nov 18, 2013)

Thanks. After doing some more research, your probably right in replacing the fixtures. I was expecting them to be a little more expensive, but $15 isn't bad.


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## PSG-1 (Nov 18, 2013)

Based on the corrosion and the bulbs being stuck, I'd agree that this is likely the issue.

2 great things for troubleshooting trailer lights are a continuity meter, for checking each wire on the harness, and one of the little tester plugs with LED's that plugs into your vehicle's trailer light socket. The LED's will come on when brakes, running light, and turn signal circuits are activated. 

These 2 things will save hours of turd-hunting for wiring problems. :mrgreen:


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## BigTerp (Nov 18, 2013)

Thanks!! I found a set of left and right lights on Ebay for $15 shipped. Not bad at all. I'll probably grab those up. Yeah, the bulbs are definetly corroded at the connection. I couldn't even get the one I busted out with a pair of needle noses. I'll look for one of those tester plugs as well.


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## PSG-1 (Nov 18, 2013)

Your lights must be mounted to the trailer frame, for the corrosion to have attacked the guts like that. This is why guides are a great thing, they keep the lights up out of the water, and it puts them higher, making your rig more visible to traffic behind you. Also, the guides are nice for backing an empty trailer down the ramp, so, you never lose sight of it.


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## BigTerp (Nov 18, 2013)

Yes, my tail lights are mounted to the trailer frame behind each fender. I have side bunks on my trailer, so I'm not sure how easy/difficult adding guides with lights would be. I also beat up my side bunks pretty good loading the boat back on the trailer, so I'm afraid I'd destroy a pair of guides rather quickly.

What is the "proper" way to treat non submersible tail lights? Unhook before backing the trailer into the water? Anything I can do do better waterproof them? I use dielectric grease on all my connections. This was the first time I've tore into the trailer lights though, so never did anything with them. I'll be sure to add a bit of grease to everything once I get some new fixtures.


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## earl60446 (Nov 18, 2013)

You should definitely unhook the lights before backing the trailer into water.
Try to keep the water out of the lights completely. Might be real hard to do though if you submerse it all the time, raising them up so they don't submerse is best. Use grease on those bulb sockets, they are the first thing to corrode. I don't know what kind of guide-ons you are thinking about but the ones on my boat would guide on a battleship they are so well built and yes my lights are at the top of them.
Tim


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## TNtroller (Nov 18, 2013)

They do make "watertight" light fixtures, which work fairly well, but the gasket(s) can fail. I've still got the original lights on my tracker trailer, I do un-plug the lights before launching, and don't hook 'em back up until I'm leaving the ramp lot. Are the ones you ordered from ebay "watertight", and seal with gaskets. Periodic inspection or treatment with di-electric grease can help, but time and elements do take their toll. Just consider it an expense of having a boat.


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## fish devil (Nov 18, 2013)

:twisted: Get yourself a set of sealed submersible LED lights. You will never have to unplug ever. Mine are still going strong after ten years of use.


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## BigTerp (Nov 18, 2013)

Thanks for the advice!! I haven't ordered my lights let, but the ones I'm eyeing on ebay are the same ones on my trailer now. They are Peterson non submersible. I'm considering submersible leds. I've converted all the lights I can in my truck to leds and really like them. I'll probably go the cheap route for now and upgrade the whole trailer to leds when the time comes.


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## BigTerp (Nov 19, 2013)

Was looking at LED tail lights last night, and found a few that seem nice. Most "kits" only come with the tail lights and wiring. Seems like a silly questions, but would I just connect my current side markers to the proper wire that comes with the kit?


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## PSG-1 (Nov 21, 2013)

I have yet to see a set of truly waterproof trailer lights. They might work for freshwater, but here in saltwater, nothing is immune from the destruction. You could fill the whole light up with dielectric grease, seal the lens with 5200, and it will still find a way for water to infiltrate, corrode and fail.

This is why I'm a firm believer in putting the lights up on guides.


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## BigTerp (Dec 9, 2013)

Got my replacement lights and installed them over the weekend. Both tail lights work now, but the passanger side doesn't work for turn or stop. All other lights and functions work fine. Any ideas what the issue could be? I'm waiting for my 4-prong circuit tester to come in, but I'm guessing the issue is on the trailer end.


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## crazymanme2 (Dec 9, 2013)

I'd double check the plug first.


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## JL8Jeff (Dec 9, 2013)

I thought the wiring or lights were going bad on my trailer and then noticed the same problem on my other trailer. It could depend on your vehicle, but my 2001 Silverado has fried 2 of the taillight converters so far. Both trailers were fine and I know the lights were working earlier in the summer. So who knows when the converter went bad.


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## nlester (Dec 10, 2013)

I bought new lights for my trailer and after I wired them up, I had the same problem that you originally encountered. My left light would light but not flash or signal a stop. It turned out that someone at the factory had managed to jam the bulb into the socket incorrectly and the bulb was 180 degrees out, I took the bulb out, bought an new one, put it in correctly and it has worked for several years. This was after spending several hours troubleshooting the problem.

A good light fixture would not let you put the bulb in wrong.


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## BigTerp (Dec 11, 2013)

Still waiting on my circuit tester to come in. We've gotten nearly a foot of snow and a half inch of ice in the last 72 hours, so I haven't had the chance to mess with anything. One thing I do have a question about is how to remove the main lights from the fixture? The side marker lights pop right out, but I couldn't get the main bulbs out. Do they need rotated first then you can pull them out? I didn't want to yank on them to hard and bust brand new bulbs in my new light fixtures.


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## Stumpalump (Dec 11, 2013)

I saw a Tee-Shirt that said "Boat trailer lights are not supposed to work." I've never owned a trailer that did not need constant attention to the lighting. Even one I redid with all the best stuff got backed into by a buddy breaking a light, had the ground wire for the break ripped by road debris and now the connector up front is cracking. I thought I was doing it once and for life. Never gonna happen. :roll:


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## JL8Jeff (Dec 11, 2013)

Some of the bulbs are push in and rotate to get them out, they are kind of spring loaded.


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## bcbouy (Dec 11, 2013)

check your tow vehicle fuses. i have submersible led lights on my trailer and i still pop a fuse a couple times a year because i'm too lazy to unplug.


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## BigTerp (Dec 11, 2013)

[url=https://www.tinboats.net/forum/viewtopic.php?p=336319#p336319 said:


> bcbouy » Today, 2:58 pm[/url]"]check your tow vehicle fuses. i have submersible led lights on my trailer and i still pop a fuse a couple times a year because i'm too lazy to unplug.



Fuse it was. Checked it today after work and it was burned out. Popped a new one in and all is good.


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## nlester (Dec 12, 2013)

You need to push in on the taillight and rotate it to get the bulb out of taillights. Your turn lights should have 2 bayonets that stick out of the bulb base, on high and one low. The bayonets must match the slots in the light holder. Don't force them, if you have them lined up right, they rotate easily.


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## huntinfool (Dec 13, 2013)

LED!!!! We repair trailers daily and LED's are the way to go.


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## nlester (Dec 13, 2013)

I'm glad it's all working.


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## BigTerp (Dec 15, 2013)

Thanks for all the help.


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## Clint KY (Dec 18, 2013)

Here is my solution to the trailer light problem:

https://www.harborfreight.com/12-volt-magnetic-towing-light-kit-69626-8847.html

and with all the coupons in the magazines you can get them for less $.

I know the magnets only adhere to steel but it was an easy task to epoxy two steel plates on the rear seat or anywhere else that lets the lights be seen. When launching I take the lights off the boat (or the utility trailer) and put them in the back of the truck. They never get wet and are easy to work on because I can take them into the shop and put them on the bench if needed. The next thing I am going to do before the season starts is replace the bulbs with LEDs.


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