All trailer lights are out... HELP????

[SamRiley]

Took my boat out this weekend. Trailer lights were working on Friday but at some point over the weekend they stopped. I checked the fuses, connections and visible wires, but nothing appears to be out of order. How do I trouble shoot this? I've got a meter but need to learn how to use it. This may be the occasion.

Any tips you could offer would be greatly appreciated :)

[Bob Parsons]

Sounds like a problem with your ground.

Check to see if there is corrosion where it is connected to your trailor.

Check same for the pins on your connectors.

[Frisbie]

Sounds like a ground issue...did you leave them on when launching the boat??

[greenacres]

my lights always work better on the way home after a good salt bath, :)

[greenacres]

just kidding try hooking up to another trailer that will narrow it down to truck or trailer.

[SamRiley]

Sounds like a ground issue...did you leave them on when launching the boat??

The trailer was connected from Friday - Sunday. When you guys say "a bad ground", how many should I be looking for? One at the coupler and one for each light?

[Mark Cahill]

are often just connected from the lights to the frame of the trailer. In my way of thinking, a bad practice, esp. with galvanized trailers. This means that the circuit is actually completed by the ball/tongue connection. Hence a bit of dielectric grease might resolve the issue.

Since it knocked out all the lights, it is an overall grounding issue, not a fixture issue.

To tell if the trailer is grounded to it's own frame, take a look at one of the lights. If it has a wire that runs out and hooks up to a screw in your frame, probably one of the ones that holds the light onto the trailer, it's been grounded to the frame.

Best practice for trailer lights:


Light bars rule...they never get wet and tend to last longer.
Learn to make excellent electrical connections. I prefer to make soldered connections, which I coat with liquid tape then shrink wrap. You can also get some nifty crimp on shrink wrap connectors at West Marine, but I prefer the old fashion way. FYI, when using shrink wrap, remember to slide it up the wire BEFORE soldering. :brow
Always carry a crimp on electical connector kit, spare bulbs and possibly even a spare light. A spare tire, spare bearing kit, usable jack (hint: your car jack is probably useless on your trailer). You'll also need the electrical kit on the boat, in case of electronics failure.
Learn to use the meter. Set it to 12 volt, hit a hot wire and a ground and the needle should move to some where around 12. Be aware that with batteries, you're not going to be able to crank your motor with 11 volts. It's not like a fuel tank.

I suggest going to a competent mechanic who'd be willing to let you stand behind him. Ask him to show you how the electric system works, and how to swap out a bearing. It'll cost, but it's knowledge you'll be glad you have late some night on your way home.

If it wasn't Mothers Day this weekend, I'd offer to come down and give you a quick run through on the wiring end.

[Ray]

Sam,

Take a look at where your gound wires are. You may have corrosion buildup. Also, tr not to leave your electrical connection made for so long after exposure to water. The water in the connector (some may get in) will evaporate and leave slat deposits, not good for electrical connections.

You can use the meater to see if you are getting power to the connector. Keep in mind it's a 12VDC system.

[mansfieldsign]

Sam, Couple of things -- Check for a broken pin on both Male/Female plugs at the car and trailer first.
Also, check the ground lug on the trailer tongue (white wire) sometimes the
wire will break at the crimp sleeve.
If those look ok check the back of the plug on the vehicle where the wire
bundle enters into the plug -- try moving the bundle slightly and then try the lights again. Salt spray and corrosion may have enter the connector if it is under the vehicle. If you have and SUV and go from a 7way to a 4 flat --make sure the adapter didn't bend or push the pin into the connector. WalMart(trailer dept) sells a neat LED flat Male test connector for a couple of bucks that will give the ok at the vehicle.

[Blackjack]

...and if all else fails the good people at Drinkwater Trailer in Pembroke make a living out of fixing problems like these. They are excellent. Of course, your problem is how to get a trailer with no lights to Pembroke...

[Mark Cahill]

Isn't a tremendously tough job. Takes me about 3 hours to do on mine, I generally do it every few years, just to be sure...

Sam, what's the status? Have you figured out your problem?

[SamRiley]

Still working on it when I have the time. All of the pins appear to be in order. What I want to do is try hooking up another trailer to see if it is the car or the trailer. There is a guy around the corner from me who trailers two jetskis and I should probably introduce myself. Bass Pro sells a little $3 tester but I don't want to pay shipping on something that low.

[stripah]

I had a similar problem last season and i found the plug tester at Wal-Mart real cheap.

[ruge13]

Sam I have a good Multimeter. We can play with it on Saturday if ya want. Shouldn't take long to figure it out...

[SamRiley]

Yup, I know that Walmart has them but I refuse to shop there.

Walmart is evil (#$112)

They intentionally offer some products under cost to draw in customers and eliminate competition. I'd much rather pay a reasonale price to a local shop. Anyone know of a local shop that stocks these?

[Ray]

Try your local autoparts store. Most sell inexpensive meters and continuity indicators.

[smallboat4]

Not to be a Jerk...but is it the bulbs? Mine will blow sometimes if I leave the lights on when backing down...

[Mark Cahill]

and have Shaun bring over the Multimeter. You need to learn to use one, as a boat owner. Also, it will allow you to fully trace the issue. I might be able to sneak out Saturday aft. to have a look at it.

[mansfieldsign]

Hi Sam, A camping RV dealer would probably have the LED socket tester.
This is a stupid question so I apologize --Did you change the trailer bulbs in the brake lights just for chuckles?. Don't just go by the side marker lamps, they usually have filiment contact sockets and they're not that reliable anyway.

[SamRiley]

Updates:

Well with a new set of LED trailer lights and a new wiring harness for the truck and about 150 clams, my lights are once again working. How the heck I corroded the Ford installed wiring in after fewer than a dozen trailer trips is beyond me. A few friends at work suggested greasing the connections with either hub lube or WD40. I'll try the lube and see how that goes. I also picked up one of those testing gadgets to tell if your truck wiring is working. Well worth the $3.00.

Tight lines and excellent fuel economy for all,

Sam

[mansfieldsign]

Hey Sam, Have a great and safe (long) weekend OTW.

[zimmjas]

Wal*Mart is evil? The heck with shopping there, try being one of their vendors. --124-3