Trailer Light Indicators

[damason]

Sometimes when trailering my C-Dory 25 a friend following me later says that my trailer lights are not working. This really concerns me as I want my lights to be working all the time. In the day time there is no way to tell if they are working or not. At night all I can see is the clearance lights.

I came up with an idea: Install LED lights on the trailer fenders to show the running lights, stop lights, turning signals, and emergency flashers. I bought the yellow/orange LED lights from Radio Shack. They have a 90 degree display angle and are pointed straight forward. They also help as clearance lights. I wired them into the trailer wires at the front of the trailer. I used heat shrink fittings to keep out water and corrosion.

LED Light Package data


LED Light and receipt showing cost of $1.99 per LED light


Installation of LED lights


Looking in the rear view mirrors


When trailering day or night I can visually check my trailer lights anytime by looking back. The outboard LED light is a running light and the inboard LED light is the stop light, turning signal, and emergency flasher.

[smittypaddler]

That'll be my summer project. It's annoying, having to run around the trailer to check lights, and I have a certain length 2x4 to press the brake pedal, all of which can be avoided!

[rogerbum]

So I assume these are wired in parallel to the lights. If so, this will indicate that the connection to the trailer wiring is solid but won't indicate that the lights are working. To do the latter, you would need something in series with the lights so that when a light filament is open (or a wire is open someplace in the circuit) OR something in parallel that only lights when there isn't a voltage drop across the filament. Then you would know when the lights are not working. VW does this somehow on their newer vehicles such that an indicator light comes on when there is an open in any light (they the owner has to figure out which light isn't working).

[Captains Cat]

Roger, one old Volvos had a dash light that did that. Sometimes hard to figure out which light was out...

And with those lights on the trailer, you may need indicator lights to tell you if the indicator lights are working.

I think I'll just stop and check. If it's a turn signal that's out, you may get a "fast" blink on your dash indicator. If it's a brake light, the same may happen if you put the hazard flashers on. If it's the tail or running lights, you can see that on the trailer.

Lots of ways to kill that bird.

Neat idea though!

[Matt Gurnsey]

AN easy wy to check trailer lights is to turn on the headlights and the emergency flashers. Walk around the trailer, and every light should be working. The emergency flashers activate the same lights as the turn signals and brake lights.

[journey on]

That "walk around" Matt suggested is important, especially for us older folks. You'd be surprised at what was forgotten: safety chain, lights, ladder, antenna up. And remember the favorite of the CHP: the break away wire. The walk around is one thing I try to remember.

After working with indicator lights for years, I think that they only show that the indicator light is working.

Boris

[Jeff & Mimi]

[thataway]

We tow a Honda Pilot behind our RV at least 10,000 miles every year, plus towing boat trailers. We stop every two hours and do the "walk around"--also before we start off. Included in this is having the flashers on--which will indicate of brake and turn lights are working.-temp of tires, hubs and brakes, as well as checking the running great and hitch.

[damason]

YES! I agree that you can tell that the trailer lights are working by doing a walk around. I do a walk around and check the lights when first hooking up the trailer to the tow vehicle. I also stop every hour or so and do a walk around to check that the lights are working.

However I cannot do a walk around while driving 60 miles a hour down the road. The Trailer Light Indicators are to give you a warm fuzzy feeling that they are still working while driving.

They are hooked up parallel to the trailer lights.

I hope this idea helps some of you C-Brats that would like this feature on your trailer.

[smittypaddler]

It's been a long time since I took shop in high school, but wouldn't the circuit below let the led indicator be lit only when the trailer light is working? The led light and resistor are in parallel, and that parallel circuit is in series with the trailer light. The resister in parallel with the led means the led only gets the .001 amp (for example) it needs.

.........I--.001 amp led-------I
neg---I..............................I---trailer light---pos
.........I--.001 ohm resistor--I

This is after edit: I had trouble with spacing (this must be variable size font), in my drawing, so I've added periods (.) to make things align. Hope that makes it look like I want it to. Just pretend the periods are spaces, and the hyphens and I's are wires. This gets more confusing the more I try to fix it.

Oops, that should've been ohm instead of amp on the resistor.

[damason]

Na Waga. Thanks for the info. Draw a schematic of the circuit and scan it into a picture on your computer or take a picture with your digital camera. Transfer the ditital camera picture to your computer. Include the picture of the circuit in your post. You will need to put the picture into your C-Brats Picture Album. If you do not have a Picture Album ask the C-Brats administrator to make one for you. Then this schematic will be very clear to all readers of this Forum.

I have worked many years in electronics and understand your circuit, however there are many people that do not know ohms from apples. Thanks again.

[smittypaddler]

Here's a picture, I hope:



Fun, doing this with the GIMP (Graphic Image Manipulation Program).

[tomherrick]

Nice solution, Dave.

[damason]

Thanks - Na Waga. Very good schematic.

[hardee]