rewiring my boat trailer- simple questions.

[DZink24]

help out a member that has very limited wiring knowledge. due to the FCM in my '04 being fried, i have no running or clearance lights on my boat trailer. so what i have devised is that i have installed 2 separate running lights on the frame of the trailer, next to the OEM ones, and will be running separate wires (brown and yellow) from those lights to the battery on the boat. my question is, what gauge wire do i need to safely complete this? i did a trial run with some wire thinner than the wires on the lights, and basically melted them. #@$%!

i figure this is better than spending the big bucks to have the FCM replaced, to only quit again in a few months.

 

[B.G. Smith]

The wireing on a boat trailer is 16ga. or 14ga. going to the tail lights. If you wired up so the stop light and tail light bulb stayed on continous you would need probably 12ga. If you just run a ground and the brown wires 14ga will be fine. The yellow wire on boat trailer is left turn/brake light. Green is the other side turn/brake light, brown is running lights, white, ground. Did I thoroughly confuse you??? bg

 

[DZink24]

ok, thank you. i will do the 12 ga. , and use alligator clips or wing nuts to complete the circuit. i will only be using this setup when i leave early in the morning or late at night to go fishing. all the other lights are fine. now to just remember to unhook the lights before putting the boat in the water. . #@$%!

and as a side question, how much juice do you think 2 taillights would use from a deep cycle trolling motor??

 

[B.G. Smith]

If the lights you installed have the 1157 or 2057 bulbs the low(tail light) element pulls about . 59 amps per bulb. Two together would be just over one amp and in one hour would amount to about 1. 2 amp hours so unless you tow a long way it won't be much drain. bg

 

[jelag]

I owned several trailers we used commercially... they all had a standard 12V battery and a 12 gauge wire to charge them... when we pulled the beds on the trucks and made flat beds out of them we tied into the current light circuits at the back of the truck and ran that wiring to a junction box on the trailer...

A 12 gauge wire fed the junction box on the trailer from the trailer battery, and we used the wiring from the truck to trigger some 12 volt relays... so the power to the lights ran from the trailer battery through the relays to the lights...

Large plastic box with an o-ring seal, all the fuses, relays were in that box on the trailer. .

All the clearance lights were LED lights... we usually had 12 to 14 of those and 4 sealed stop/tail lights, (NOT LED) and (2-3) 35 watt tractor floods for back up lights. .

We didn't use LED's for the stop/tail because in the winter the LED's weren't hot enough to melt off the snow... we'd use the light bulbs sealed in a 4" round lens...

all connections were with butt connectors and shrink tube with sealant in the tube... we'd run most of the wires thru either PCV tubing or conduit so that the snow load in the winter couldn't pull them down...

We'd see several hundred thousand miles on these trailers before they were replaced... OH YEA, where the lights plugged into the wiring harness we'd either use Vaseline or dietetic grease...

so we bypassed all the factory truck stuff, and made it old fashioned, and dependable and very simple to trouble shoot...

Hope this helps...

 

[DZink24]

thanks for all the relies so far, but i may not need to after all. i went and got a 20 amp fuse today after seeing that #33 in the fuse box was smoked (trailer park lights). so i plug in the new fuse and i'll be... the lights work... . for now. they are a bit dim (i'll recheck after the sun sets to be sure) so i believe that means a short somewhere, but thats a heck of a lot cheaper to hire a mechanic to find and fix that than it is for the dealer to replace the FCM/IPM. so i am not giving up on the wiring project. .

 

[Alaskaskiff]

I took an extra precaution when I rewired my boat trailer that is working well now. I ran a ground wire for the lights as well and did not use the trailer for any grounding purposes at all. I had dim lights and found that that one of the hot wires had rubbed through inside the frame (galvanized trailer) and was shorting. The lights work better now and having one wire chafe will not trash the system.

Just remember: Shortly after man invented the wheel, he invented the trailer, and ever since he has been trying to hook up the lights!

Good luck