Trailer Light Question

hazelnut · 03-09-2006, 06:19 PM

Hello all,

Looking for a little bit of help here. Just finished rewiring my trailer. Of course this is a pretty simple process... The wiring part. Brown to Brown Green to Green Yellow to Yellow etc. Anyway, I finished the job plugged it in and jackpot everything lights up as it should (sidelights, rear lights etc) Drivers side blinker works Bright Dim Bright Dim etc. Then the passenger side bright OFF bright OFF Bright OFF hmmmmmmm then the brakes, Driver side no problem passenger side OFF!?!?! Take the foot off the brakes and both light up dim as they should. Any ideas????

Skip · 03-09-2006, 06:28 PM

.....double check the ground connection for the right side tail lamp assembly.

The majority of wiring issues on trailers always seems to ccome back to grounding issues, perhaps the ground was disturbed when you were rewiring...

Skip

jrc · 03-09-2006, 07:05 PM

or one fillament in the on the passenger side bulb is burned out.

JTA · 03-09-2006, 08:34 PM

Remove the bulbs and make sure there's no corrosion or rust. Try switching the bulbs to see if the same problems show up. Or, buy a new trailer.

Misty Blue · 03-09-2006, 09:19 PM

Hazelnuss (sorry my mother was from the black forest):

Good advice from all.

I have four trailers and often use my truck to pull other boats; friends, CG, etc.

I found that keeping up lights on multiple trailers was a real pain in the neck with corrosion and sometimes daily immersions. A CG buddy put me on to a good idea. With his advice I made a "trailer light bar" out of 2" PVC. It is correctly made up and removable from the trailers.

When I tow the Misty I tie it on to the swim platform. The 25' connecting wires installed in the bar go right to the trucks light plug. When I tow the Deb's Joy it goes on the back of the boat (tie downs are already installed in the bar) with the same electrical hook up.

The bar is removed prior to launching and so it never gets submerged. When not in use it is tied to the side of the pickup truck. No mater what I am towing or when I may need to tow a trailer I know that I have the proper lights.

Pretty cool idea, even if it did come from a Boatswain.

Misty Blue

islandAl · 03-09-2006, 10:22 PM

How does the bar on the back of the boat illuminate the license plate?

66WINN · 03-09-2006, 10:51 PM

I would have to agree with Skip and jrc. The other thing to double check would be your green wire as this is the one that controls the brake and turn signal on the passanger side. See the attached link for a wiring diagram.

http://www.etrailer.com/faq/wiring.asp

Last year I rewired my trailer and replaced all the lights with LED. They use less voltage and don't heat up the way incandescent bulbs do. That makes them better for submersion as the hot incandescent bulbs tend to burn out if they come in contact with water. The LED's also give off a brighter light.

Mee-n-Mac · 03-10-2006, 12:22 AM

You've got a bad ground on the passenger side socket. Do you have an ohmeter or some other circuit tester you can use ? I can talk you through it if you want but I'll guess if you look close enough you'll find it anyway. What's happening is that there are 2 filaments in the bulb which are tied together at one end, which is supposed to be connected to ground (imagine a Y with the bottom tied to ground). Turning on the running lights applies 12V to one filament and there's just enough grounding to allow current to flow through the filament to get it to glow (but I bet it's dimmer than normal). When the blinker or brake is turned on the other filament gets 12V and now you've got at least 2X the amount of current trying to go through the bad ground. Because the ground is poor the voltage at the common end of the bulb rises. Now you've got a bulb with 12V at both tops of the Y and mebbe 8-10V at the bottom of the Y. Not enough current flows to make either bulb glow so it/they go out (or glow verrrry dimly

). Clean the socket or bulb (no rust allowed !) or check for loose wiring to that socket.

03-09-2006, 06:19 PM	#1
hazelnut Senior Member Join Date: Oct 2003 Posts: 1,348 Blog Entries: 3 Thanks: 508 Thanked 462 Times in 162 Posts	Trailer Light Question Hello all, Looking for a little bit of help here. Just finished rewiring my trailer. Of course this is a pretty simple process... The wiring part. Brown to Brown Green to Green Yellow to Yellow etc. Anyway, I finished the job plugged it in and jackpot everything lights up as it should (sidelights, rear lights etc) Drivers side blinker works Bright Dim Bright Dim etc. Then the passenger side bright OFF bright OFF Bright OFF hmmmmmmm then the brakes, Driver side no problem passenger side OFF!?!?! Take the foot off the brakes and both light up dim as they should. Any ideas????

03-09-2006, 06:28 PM	#2
Skip Senior Member Join Date: Apr 2004 Location: Dover, NH Posts: 1,615 Thanks: 256 Thanked 514 Times in 182 Posts	Possible ground problem.... .....double check the ground connection for the right side tail lamp assembly. The majority of wiring issues on trailers always seems to ccome back to grounding issues, perhaps the ground was disturbed when you were rewiring... Skip

03-09-2006, 09:19 PM	#5
Misty Blue Senior Member Join Date: Jul 2004 Posts: 658 Thanks: 121 Thanked 283 Times in 98 Posts	Trailer lights Hazelnuss (sorry my mother was from the black forest): Good advice from all. I have four trailers and often use my truck to pull other boats; friends, CG, etc. I found that keeping up lights on multiple trailers was a real pain in the neck with corrosion and sometimes daily immersions. A CG buddy put me on to a good idea. With his advice I made a "trailer light bar" out of 2" PVC. It is correctly made up and removable from the trailers. When I tow the Misty I tie it on to the swim platform. The 25' connecting wires installed in the bar go right to the trucks light plug. When I tow the Deb's Joy it goes on the back of the boat (tie downs are already installed in the bar) with the same electrical hook up. The bar is removed prior to launching and so it never gets submerged. When not in use it is tied to the side of the pickup truck. No mater what I am towing or when I may need to tow a trailer I know that I have the proper lights. Pretty cool idea, even if it did come from a Boatswain. Misty Blue

03-09-2006, 10:22 PM	#6
islandAl Senior Member Join Date: Feb 2004 Location: Mountonboro Posts: 200 Thanks: 12 Thanked 0 Times in 0 Posts	license plate light How does the bar on the back of the boat illuminate the license plate?

03-10-2006, 12:22 AM	#8
Mee-n-Mac Senior Member Join Date: Sep 2003 Posts: 1,943 Thanks: 23 Thanked 111 Times in 51 Posts	It's a bad ground You've got a bad ground on the passenger side socket. Do you have an ohmeter or some other circuit tester you can use ? I can talk you through it if you want but I'll guess if you look close enough you'll find it anyway. What's happening is that there are 2 filaments in the bulb which are tied together at one end, which is supposed to be connected to ground (imagine a Y with the bottom tied to ground). Turning on the running lights applies 12V to one filament and there's just enough grounding to allow current to flow through the filament to get it to glow (but I bet it's dimmer than normal). When the blinker or brake is turned on the other filament gets 12V and now you've got at least 2X the amount of current trying to go through the bad ground. Because the ground is poor the voltage at the common end of the bulb rises. Now you've got a bulb with 12V at both tops of the Y and mebbe 8-10V at the bottom of the Y. Not enough current flows to make either bulb glow so it/they go out (or glow verrrry dimly ). Clean the socket or bulb (no rust allowed !) or check for loose wiring to that socket. __________________ Mee'n'Mac "Never attribute to malice that which can be explained by simple stupidity or ignorance. The latter are a lot more common than the former." - RAH

03-09-2006, 07:05 PM	#3
jrc Senior Member Join Date: Apr 2004 Location: NH Posts: 2,689 Thanks: 33 Thanked 439 Times in 249 Posts	or one fillament in the on the passenger side bulb is burned out.

03-09-2006, 08:34 PM	#4
JTA Senior Member Join Date: Aug 2002 Location: Fort Pierce, Florida Posts: 233 Thanks: 34 Thanked 25 Times in 21 Posts	Remove the bulbs and make sure there's no corrosion or rust. Try switching the bulbs to see if the same problems show up. Or, buy a new trailer.

03-09-2006, 10:51 PM	#7
66WINN Senior Member Join Date: Jul 2005 Location: Massachusetts Posts: 58 Thanks: 7 Thanked 4 Times in 2 Posts	I would have to agree with Skip and jrc. The other thing to double check would be your green wire as this is the one that controls the brake and turn signal on the passanger side. See the attached link for a wiring diagram. http://www.etrailer.com/faq/wiring.asp Last year I rewired my trailer and replaced all the lights with LED. They use less voltage and don't heat up the way incandescent bulbs do. That makes them better for submersion as the hot incandescent bulbs tend to burn out if they come in contact with water. The LED's also give off a brighter light.