Trailer wiring fries fuse

[vroom ZOOM]

Probably a common thing, but for some reason I couldn't find anything on the internet or forum about this. After pulling my boat out of the water and after that connecting the trailer lights, the running lights work for maybe 10 seconds and then the fuse blows. Before launching the running lights work great. After pulling the trailer from the water the brake and turn lights work, but the fuse for the running lights blows. I always unplug the wiring before backing the trailer into the water. The lights are incandescent, the trailer is a trailmaster T2050BR

 

[Scott Danforth]

you may have a light fixture that is filling up with water and shorting out

 

[dingbat]

Unplugging only helps if your blowing bulbs from water intrusion. It will not stop a fixture from shorting.

In this day and age there is no excuse for not have hermetically sealed lighting on a boat trailer.

One of your running lights is leaking

 

[mike_i]

Next time you launch after pulling the trailer out of the water see if the lights are draining water, if so there's your problem. What's the value of the fuse?

 

[gm280]

I am not so sure water is your total problem. I mean a water filled light isn't a direct short. The water doesn't carry current like a piece of wire and therefore it has some resistance with it. So you could have a fuse that is on that very edge of current carrying ability and blowing for the little bit of extra current with the water across the terminals. JMHO

 

[JimS123]

You have a stripped wire that is either touching ground or another wire. If you have a swing tongue, look there first for a pinched wire.

 

[vroom ZOOM]

You have a stripped wire that is either touching ground or another wire. If you have a swing tongue, look there first for a pinched wire.

Then why does it only happen when the trailer gets wet? The swing tongue doesn't get in the water. IMO if it was there then the problem would happen all the time? I will check anyways and add a sleeve maybe to prevent this possibility in the future though.

 

[vroom ZOOM]

I am not so sure water is your total problem. I mean a water filled light isn't a direct short. The water doesn't carry current like a piece of wire and therefore it has some resistance with it. So you could have a fuse that is on that very edge of current carrying ability and blowing for the little bit of extra current with the water across the terminals. JMHO

I was thinking the same thing. The fuse is a 10 amp, I tried a 15 but it also blew with a pop.

 

[vroom ZOOM]

you may have a light fixture that is filling up with water and shorting out

I think so too. I will try take each one out on my driveway and put each one in a bucket of water and see when the fuse blows

 

[JimS123]

Then why does it only happen when the trailer gets wet? The swing tongue doesn't get in the water. IMO if it was there then the problem would happen all the time? I will check anyways and add a sleeve maybe to prevent this possibility in the future though.

I didn't say it was the swing, I said look there FIRST. Because that's the easiest to rule out. If you have incandescent lights, change them out second. Just because. It will eliminate problems down the road. No need to even test them. While you're at it, look at every place where a wire goes thru the frame.

 

[camper4lyfe]

I was thinking the same thing. The fuse is a 10 amp, I tried a 15 but it also blew with a pop.

Never put a higher amp fuse if a lower amp fuse is blowing. You run the risk of causing bigger issues.

 

[Captain Caveman]

Never put a higher amp fuse if a lower amp fuse is blowing. You run the risk of causing bigger issues.

Agreed. We've all probably done it once, but that's how you melt wires or cause a fire.

The water may be getting in and moving an exposed wire to touch metal. Definitely check all of the wiring. When I've had issues, I disconnect the wires at the lights. Then I tie a string and pull the wires from the tongue. With everything out I can see where the bad wire is. Most often I just run a new set of wire which is a cheap solution and fix.

 

[RogerV]

If you replace the lights use the sealed led lights and heatshrink splice connectors also silicone in the connectors works great also a bad ground can cause blown fuses also. on my crab boat i put the lights on 2 pin connectors and remove them when launching. going on 8 yrs still no problems