Installing A 3rd LED Brake Light In A 2-Wire System Designed For Incandescent Bulbs

Updated 06/09/2017 | Published 06/08/2017

Products Featured in This Question

2-to-3 Tail Light Converter for Towed Vehicles w/ Incandescent Tail Lights

(174)

$41.09

Load Resistor Kit for LED Turn Signals - 50 Watts - 6 Ohm - Qty 2

(37)

$13.77

Question:

I have a 2010 Silverado 2500 HD towing a 30 ft. travel trailer. Trailer has four round trucklite type lights in rubber grommets. These were replaced with very nice LED units. Two on the left operate as tail/turn/brake lights as does the right side. Now I added a LED third brake light bar up higher for some additional safety. When I was doing this I could only find a off brand converter and didnt know about the LED being an issue with these converters. I ended up with a system that works normal until you turn the tail lights on. Thats when the third brake light starts flashing with the directional in use while dimly lighting four of the many Leds in the opposite tail light. The more I looked into it I saw these little notes on sites about not working with the LEDs, and now the use of diodes to prevent back feeds. If I have to replace the converter with a better unit, so be it. Im a little unsure where to put a diode/s in my system. The wiring diagrams on your site seemed to have separate amber turn signals on the trailer where I have two working together. Can you share any advice based on me putting a #118158 in the system ? If this question looks familiar, I sent it to you 4-5 days ago but gave you the e-mail wrong. Thanks

asked by: Kevin S

Helpful Expert Reply:

When you turn on the running lights there is more of an amperage draw so that is why the system changes at that point. For your 3rd brake light, I recommend first disconnecting it from your current wiring. Then I recommend using the Vehicle to Vehicle Tail Light Converter # 118158 to splice into your combined right/stop and left/stop wiring. Then connect your 3rd Led brake light to the stop output on the converter. If there is hyper flashing on that third brake light at that point, then install the Putco LED Light Bulb Load-Resistor Kit - Aluminum # DI34ZR between that converter and the light. This creates a stronger draw like incandescent lights need to make your LED lights compatible. You may choose to install these load resisters in line of your other LED lights as well if they have issue. I recommend this over the diode option you mentioned.

expert reply by: Jason S