Stop,Turn,Tail LED PROBLEM

[Wardinbb]

Hi All,
I'm in need of some figurin' out here.
I picked up a pair of 7" LED stop, turn, tail lights for my '64 TradeWind. The problem is when the new LEDs are both hooked up, the turn signal causes both LEDs and the truck lights to blink!

Here's how it went. The LED has 3 wires, ground, tail, stop. Starting on the trailer curb side I taped the LED to the trailer to test the LEDs before installing. Grounded the LED with a screw to the trailer body. Twisted the ends of the trailer Stop and Turn wires together and connected to the LED stop wire. Connected the Trailer Tail light wire directly to the LED Tail wire. All functions worked properly.

That was easy! But as the sun set in the West, I thought I'd test the left side as well. Hooked up the left side in the same fashion. Running/tail LEDs were fine, brake light LEDs were fine. When I put on the left blinker, both LEDs blinked AND both of my truck lights blinked too! Same story with the right blinker. I then started switching wires methodically with no solution.

I checked the wiring diagram for the trailer, confirmed trailer and truck wire colors and all appears proper. I searched the Forum and found 2 items that may come into play. One is the reference to a Resister and the other is to the Flasher. Can this problem be fixed by replacing the flasher in the tow vehicle? Or does a Resister need to be added to the LEDs? Or did I just wire the LEDs wrong? And how come the right side worked fine until both sides were hooked up?

So there you have it. Can anyone shine some light on this for me?
Thanks,
Ed

[59toaster]

Originally Posted by Wardinbb

Hi All,
I'm in need of some figurin' out here.
I picked up a pair of 7" LED stop, turn, tail lights for my '64 TradeWind. The problem is when the new LEDs are both hooked up, the turn signal causes both LEDs and the truck lights to blink!

Here's how it went. The LED has 3 wires, ground, tail, stop. Starting on the trailer curb side I taped the LED to the trailer to test the LEDs before installing. Grounded the LED with a screw to the trailer body. Twisted the ends of the trailer Stop and Turn wires together and connected to the LED stop wire. Connected the Trailer Tail light wire directly to the LED Tail wire. All functions worked properly.

That was easy! But as the sun set in the West, I thought I'd test the left side as well. Hooked up the left side in the same fashion. Running/tail LEDs were fine, brake light LEDs were fine. When I put on the left blinker, both LEDs blinked AND both of my truck lights blinked too! Same story with the right blinker. I then started switching wires methodically with no solution.

I checked the wiring diagram for the trailer, confirmed trailer and truck wire colors and all appears proper. I searched the Forum and found 2 items that may come into play. One is the reference to a Resister and the other is to the Flasher. Can this problem be fixed by replacing the flasher in the tow vehicle? Or does a Resister need to be added to the LEDs? Or did I just wire the LEDs wrong? And how come the right side worked fine until both sides were hooked up?

So there you have it. Can anyone shine some light on this for me?
Thanks,
Ed

Are you sure you didn't get one of the running lights crossed with the turn?

Ground good between the Coach and tow?

[74Argosy24MH]

The brake lights on the truck are probably in parallel (do you have seperate brake and turn signal lights on the truck?). When you hooked the trailer brake and turn signal wires together it made one big circuit with all the lights. Unhook the brake and turn signal wires and try just the turn signal to each LED.

John

[overlander64]

Greetings Ed!

I have one thought that hasn't been mentioned in earlier posts. Were the original lights functioning properly prior to starting the LED project? If this is an unknown, I would suspect an issue with the way the Bargman connector is wired on the trailer end. The wiring schematic that was used in 1964 was somewhat different than the current industry standard, and when a connector wired to the Airstream standard is connected to a tow vehicle with the modern industry standard it can produce results similar to what you are reporting. The link below illustrates the way that my '64 was wired when I acquired it in 1995:

1964-1965 Airstream Bargman Connector Wiring Schematic

The current industry standard wiring diagram can be found in the link below:

Current Industry Standard Bargman Plug Wiring Schematic

Good luck in locating your wiring issue!

Kevin

[Rick Alston]

Ed,

John is right; at least I think he is.

I think your left turn signal is back feeding the left stop wire of the trailer that is connected to the left truck stop light that is connected to the right truck stop light that then passes current to the opposite side stop wire of the trailer; hence all stop and turn lights will flash.

This seems correct because the right side independently functions properly for stop, turn, and run but when you added the left side; the left turn signal became connected to the right side through the stop wire of the trailer. When you first looked at the right side only (no left connection), you would not notice that the right stop wire was being back fed because the back feed would go to the right stop & turn light which is the light you expected to see light up.

To test my theory, leave every thing connected and start work on the RIGHT side; disconnect the “twisted together” trailer stop and turn wires but leave the turn wire connected to the LED stop/turn wire. Activate the RIGHT turn signal and see if the trailer and truck lights flash. If they don’t flash, I am right and the turn signal was back feeding through the trailer stop wire to the truck stop lights and on to the left side of the trailer.

If they flash, disconnect the LEFT side “twisted together” trailer stop and turn wires but leave the turn wire connected to the LED stop/turn wire. Try the RIGHT turn signal once again. If they still flash, then the LED lights are back feeding the trailer running lights and on to the truck running lights.


Rick

[Wardinbb]

Thank you all, your combined knowledge and experience fixed the problem.

59toaster, Thanks for the praise, at least I got the ground right!

Kevin, Good Call. Those are the exact wiring diagrams I have on file and used to wire the truck and trailer. Its good we're all on the same page with that reference.

John and Rick, that was the trick. WHODA THUNK IT that you would not connect the trailer brake wires to new tail lights!

I tested both your directions. The tail light LEDs work correctly in all modes with left and right trailer brake wires disconnected from the LEDs. They also work correctly with only the left trailer brake wire and turn signal trailer wire combined and connected to the left LED with the right trailer brake wire disconnect from the right LED tail light.

My notes indicate that when initially wiring the truck harness that the vehicle turn lights ran with the brake wire. It now makes sense that the turn signal wires activate the trailer brake lights as well.

Final, final, no trailer brake light wires need to be connected to the trailer tail lights with these LEDs.

Now I can get back to installing the refurbished rear window back in before it rains tomorrow.

Thanks again to all,
Ed