How To Troubleshoot and Fix Boat Trailer Lights that Don't Work | BoatUS

[@otisspunkmeyer5883]

I really appreciate the prep and editing you did to be able to cover all that you did in 3 minutes. MANY videos are a 20-30 minutes and cover no more than you did.

[@boatus]

Thanks for watching, Otis! And glad you found it helpful. That gives you an extra 25 minutes of boating time! ;-)

[@mammothadventureracing]

Super simple to understand and really helpful to avoid screaming at wife and kids if the lights are working. Not too mention eliminate the possibility of a faulty towing vehicle electrical point. Easy and simple. Great video!

[@boatus]

Thanks for watching, Russell. And glad you found it useful!! And ways to keep the wife and kids happy are ALWAYS good! 😂

[@porkyrabbit]

It's youtube education posts like this that give me faith in humanity - this was extremely helpful - thank you!!

[@boatus]

We're verklempt! Thanks for watching. Glad you found it helpful

[@gregsharp8601]

THANK YOU! I've gotten increasingly frustrated with bad troubleshooting videos. Yours is very well done. I appreciate you taking the time to make this. God bless!

[@boatus]

You are very welcome, Greg. Thanks for watching!

[@gerardwade4192]

Thank you....most of the other videos only show the vehicle end...you went the extra mile and showed where the real issues usually are. . thanks

[@boatus]

Glad you found it helpful, Gerard!

[@tompavic5364]

Great video very precise and slow enough that us ole timers can follow, once again thanks

[@boatus]

Thanks for watching, Tom. Glad you found it helpful!

[@cra2cra226]

Great presentation. No ums and ahhs. Clear audio & video.

[@boatus]

Thanks for watching!

[@edm163]

Charles, I am forever grateful to you for your video regarding the ground. I have been trying to figure out since buying my used boat last year why my trailer lights occasionally work, usually don’t. Tonight, I found that the ground wires were not secure to the trailer. Lights & blinkers work consistently now. Thank you very much !

[@boatus]

We are SO happy to hear this, Citizen Bones! It's (not) funny how such a simple thing can be so elusive. Thanks for finding our vids, and we're glad we could help out. Have a fun, safe, and trouble-free boating season ahead!

[@aaroncoleman6647]

Yup, found a broken/loose wire!!! It was all the way in the rail. Took a while to get to it, but it worked. Thanks!!

[@boatus]

You are welcome, Aaron! Glad this helped you narrow down the issue. Thanks for watching and letting us know!

[@Buddy1980]

Just found this video and I fix my boat trailer. Thank you so much.

[@boatus]

That's awesome news. Buddy! Glad we could be of assistance.

[@seangillen1960]

I've been working on mine for a week and it has been frustrating. Think I've made every mistake possible. Good to know there's a tester for the plug in at the rear of the vehicle. Thanks. Great video.

[@boatus]

How frustrating, Sean! Thanks for watching the video. Hopefully it will help you troubleshoot the problem. Let us know if you fix it.

[@borislum1998]

dielectric grease is an insulator and protector against water. so crank down on your ground contact to make metal to metal contact.

[@boatus]

Thanks for the tip, Boris.

[@scottmckenna9164]

Whew! You touched every base. Good man.

[@boatus]

Thanks for watching, Scott!

[@jticottage]

Great video, now I know where to start with my dim right side stop and turn light.

[@boatus]

Thank you for watching! Glad we could help.

[@miltonweyer3544]

finally got someone who was to the point with steps that was not in it just to hear himself talk.

[@boatus]

Thanks for watching, Milton! 😂Glad you found it helpful and short-winded.

[@thesilentone4533]

thank you I needed to know how to test individual lights

[@boatus]

You are welcome. silent! Thanks so much for watching and good luck finding the source of your outage.

[@tuvideoloco6551]

Thanks. For taking the time to make a video.

[@boatus]

Thanks for watching, Santiago!

[@mfort9997]

Wow…soooo knowledgeable and helpful info!!

[@boatus]

Thanks for watching, M! Glad you found it helpful!

[@fishnetics7929]

THANK YOU for this video! Very helpful!

[@boatus]

Thanks for watching! Glad you found it helpful.

[@jaykokos]

Excellent video

[@boatus]

Thanks for watching, Jason!

[@jerrylanglois9489]

Left blinker and brake light weren’t working so I cleaned contacts as you suggested. Bingo! Problem solved. Thank you!!

[@boatus]

We love to hear this, Jerry! We're so glad we could help -- and even happier it was a simple fix. Thanks for sharing!

[@steveng.c.8524]

Great video

[@boatus]

Thanks for watching, Bubba!

[@RobertHeaney]

Great video, thank you!

[@boatus]

Thanks for watching, Robert!

[@itssammiesakran]

I had some rewiring done on my boat trailer yesterday. Before I dropped the trailer off, my forward wheel well lights would blink with each corresponding turn signal. Now they no longer blink. Are they supposed to or not because I'm getting conflicting answers

[@boatus]

Thanks for the question, Samantha! Those are running (marker) lights, not blinkers. It's probable the trailer wasn't wired properly in the first place, or a glitchy ground was making them blink, but they shouldn't have. By the letter of the law, turn signals are "positioned symmetrically on the rear" of the trailer, not forward of the wheels. Hope this helps.

[@richhoops2413]

Thanks for your help. Saved me some money! I "Liked"

[@boatus]

Thanks for watching! Glad you found it helpful, Rich

[@michaelkulman7095]

If you didnt have a spwre bulb socket could have been tested with meter and each wire should be tested for continutity with ground and continuity with its other end. You can have a break in a wire or a break in a wire to ground. Pretty good video though. If vehicle is there a plain test light also works.

[@boatus]

Thanks for sharing your experience, Michael!

[@Maxxrevv]

Thanks bro.

[@boatus]

You're very welcome, Maxx. Thanks for watching!

[@brianthorpe6750]

My running lights on trailer ONLY work when wet. Brake and turn work as they should.

[@boatus]

It's impossible for us to diagnose the issue from afar, Brian. We recommend going through the troubleshooting steps outlined in the video to see if you can isolate the source. There are a fairly limited number of possibilities, and we cover the most common ones. If you can't figure it out, get recommendations for a good trailer shop to help.

[@tonyoltean09]

Good video, I have a problem with my boat trailer. I have power at the truck (used tester and volt meter), I have continuity at my left light but no power when plugged in. The right light works fine. They are brand new led lights. This one really has me stumped as the right light works fine. Why would I not have power at the left even though I have continuity?

[@boatus]

Hi Tony. Sorry to hear you're having an issue. A few questions: Do the new LED lights plug in, or are they hardwired? Did you replace them with the same style that was there, or did you swap them out to LEDs? Have they had this issue since you installed them, or did this start after you used the trailer one or more times? Those answers may help us better get to a potential solution for you.

[@ryanvernatter3537]

What kind of a meter it that?

[@boatus]

Hi Ryan. It's a multimeter. You can find out how to use one by watching our video here: kzbin.info/www/bejne/hYLZkoKvaL9_gLs

[@tinosantiago4754]

Mine problem is that everything work great left, right light work and brake also but when it comes turning on the light on the back of thr headlights it dosent turn on someone know why?

[@boatus]

Hi Tino. Thanks for the question. Nine times out of 10, trailer light problems can be attributed to faulting wiring and top-of-the-tree is issues with the ground connection. Sometimes when some of the lights work but others do not it is because the ground connection on the trailer is poor. Find the position on the trailer where the ground is connected - it is often a ring terminal under a nut and bolt attached to the trailer chassis. This connection should be tight and free of corrosion. If need be, disconnect this cable, clean all the connections and reattach. Check that the plug and connector on the rear of the towing vehicle are in good shape too.

[@davidbartlettsr1241]

The video was good, probably one of the better ones I've seen, HOWEVER, you miss the mark on 2 items. 1) NEVER leave a bulb in place when performing continuity readings- the meter WILL READ THRU the bulb element. 2) when cleaning up grounds, clean EVERYTHING, that includes the bolt and or washer that pinches the solderless connector to the frame. These connections should be as clean as possible and look brand new. For the record I'm a licensed electrician and have wired dozens of trailers a d other DC related items on tractors and research equipment over the last 50 years...

[@boatus]

Appreciate your comments, David. Regarding #1, it doesn't matter if the bulb stays in place because we are testing the complete circuit, including the bulb. If the bulb is removed, we will automatically get open circuit because there's no resistance. #2, you're absolutely right. All ground connections should be as clean and bright as possible.

[@davidbartlettsr1241]

@@boatus sorry but I DON'T agree. If you are testing the circuit you ALWAYS remove the bulb. Meters - especially DVM's will read right thru a bulb and provide a FALSE reading . If a bulb is suspect, simply remove and test independently of the circuit. Once again, the video was good, well thought out and well announced, but assuming we are talking about the same thing here - a bulb is NEVER left in place during diagnostic testing, after the fact yes, just not during. I stand by nearly 50 years of electrical experience in industry. Working on trailers is not an art for a professional, but I can see why the lay person would have a problem, and thank goodness that there are videos like this for them. I'm just saying, it could use a tweak..... IMHO

[@wardpotter9599]

I also have a brown with yellow strip coming from left side of trailer light...5th wire??

[@boatus]

Hi Ward. Thanks for watching! The fifth wire is connected to the reverse light circuit on the vehicle, which, when activated, disengages the hydraulic trailer brakes when the vehicle is put in reverse. Not all boat trailers have this. -Charles

[@ColtonBlumhagen]

All my lights work except the left signal. The brake works though. (same bulb) What could the issue be?

[@boatus]

Hi Colton. Thanks for the question. Most trailer light problems are due to a poor ground - that’s the white wire that is either bolted to the trailer frame after it emerges from the plug or in some cases wired directly to the light fitting itself. If you can test the continuity of each of the cables on your trailer lights with an electrical multimeter set to the ohm scale. Disconnect the plug from the vehicle first. You may need to temporarily extend the leads from the meter to accomplish this so you can reach both ends of the cables. Test each of the four wires in turn; the meter should read 0; any number means that there is either some resistance in the cable or one may actually be disconnected, however I doubt this if the other lights work. Try swapping out the bulb, too. It could be faulty.

[@samuelpharand2593]

My trailers lights come on the turn signal don’t flash

[@boatus]

Hi Samuel. Chances are that it's a bad wire or ground. You'll have to chase down each connection (starting with the ground). If you can't find the problem, the plug is your next suspect. Good luck!

[@dram340]

Good info for trouble shooting but your use of die eletric grease is wrong

[@boatus]

You don't say why using dielectric grease is incorrect. We used it to prevent further corrosion after cleaning the electrical contacts in the trailer plug, which is perfectly acceptable.

[@boatus]

@@Nanooky Good question, but no. WD-40 is not a good substitute for dielectric grease in this situation. WD-40 is a spray lubricant, while dielectric grease has a far thicker consistency to stay in place and insulate the terminals against future corrosion.

[@pullmyfinger6932]

@@boatus > dielectric grease does indeed prevent corrosion by insulating or blocking the air and elements, however it does not conduct electricity, so it shouldn't be applied directly to the mating surfaces (pins and sockets) of an electrical connection.

[@boatus]

@Pull My Finger Technically you're correct. Dielectric is a silicone-based grease and will insulate. However, Charles spread a little on the base of the plug to keep the water out and a little on the bulb base for the same reason. Considering the amount used, we doubt very much whether this would totally insulate the pins or the bulb. If you used gobs of the stuff then it would have an impact. We have frequently used it in the method described with no ill effects. Corrosion is far more invasive and can lead to many more issues than a smear of grease.

[@vancepass7403]

Badass☆☆☆☆☆☆

[@Darbymitch101]

Watch a ghost leave your finger at 2:39

[@boatus]

I think it was a gnat. But maybe it was a ghost that was causing the electrical problems?

[@Gehqster]

“Now let’s hit the road” I’m still left with non functioning trailer lights Charles

[@boatus]

Bummer. These would be the most common troubleshooting steps to narrow down the issue. You might need to seek out the services of a technician if none of these help.

[@fidalgoisland]

Each light should have it's own ground wire run back to the main ground. I don't understand the insistence on using the trailer frame as the ground...it never lasts for various reasons. It is a simple add to existing trailers and will save many headaches.

[@boatus]

You make a valid point, Dennis, although trailers usually come from the manufacturer wired this way. If you're rewiring an entire trailer yourself, there's certainly nothing wrong with running grounds, and in the long run, doing so could save you some hassles.

[@sstatic6093]

Here’s what’s going on with my trailer lights when I plug it up it blows the fuse to my tail light but everything else works like the brake light the flasher the blinker so what’s causing it?

[@boatus]

Thanks for the question, s static. This sounds very much like a short in the trailer wiring. Assuming that you have a four-wire harness, the brown wire is the cable that powers the rear lights and I would start looking here first. Your problem is most likely due to the brown wire chafing through and making contact with the trailer chassis, which is connected to the vehicle ground through the white wire. The easiest way to track down the fault is to use a multimeter as we show in our video. Or you can search our channel for a video specifically on how to use a multimeter to isolate electrical problems. Good luck finding the problem, and let us know how you make out.

[@sstatic6093]

@@boatus I found out what was causing it which is weird I bought 2 lights that had green and brown wires didn't know that it made a difference but it did so I went back and bought a light with yellow and brown and it works smh.

[@boatus]

@@sstatic6093 Awesome news and thanks for the update. Glad it was an easy (and inexpensive) fix!

[@mrajj1261]

00:55

[@boatus]

Thanks for watching, AJJ. What about it?

[@johneunos3450]

Boat trailers lights PIA.

[@boatus]

😂They can be for sure, John. At least it's a fairly "simple" system to troubleshoot and fix. Generally no high-tech stuff involved.

[@bilstein2410]

Or even worse, no lights at all.

[@1OFGODSOWN]

LED LIGHTS are CHEAP so get off your wallet and put a completely new set on and move on.

[@iztheterrible]

not very helpful

[@boatus]

Sorry you didn't find it helpful. Anything we could have done differently that would have made it better?

[@__Gus_]

we just installed a new light kit on the trailer the light on the right side turns on but the on on the left does not turn on wires are all put the same way the others were any ideas?

[@boatus]

Thanks for the question, planest. Unfortunately it's very hard for us to know what's going on without being there in person. When one light doesn't come on, it's likely either a ground issue or a short issue. I'd start by checking all connections to ensure they're tight. (Use marine-grade heat shrink connectors anywhere that could get wet.) And also check that any wires are connected to corrosion-free bare metal surfaces. If that all looks ok, check all towing-related fuses and relays. Sorry we can't help more, but we wish you the best of luck. If all else fails, find a good trailer place near you and see if they can track it down.