Troubleshooting LED Tail Lights Not Working on Trailer

Question:

new led lights tll19rk are wired up by color code on my utility trailer. the turn signal and brake lights work fine on both fixtures, but neither tail/marker lights work except for the small dim light on the side markers. I have hooked up white wire straight to fixtures from plug, also grounded each white wire separately to trailer but no help. I hooked up each lead wire to external 12vdc source and each fixture works just fine. I swapped out 7 pin to 4 wire plug adapter but no help. Do I need an inline resistor or what? my tow vehicle is a 2013 Silverado 2500 HD.........

asked by: Steve

Expert Reply:

The first thing you should do is trace the wiring from your tail lights to ensure there are no crimped, damaged or broken wires that are causing interference with the circuit.

If you do that and find the wires are fine then I do recommend using Load Resistors # DI34ZR as this should allow the harness to "recognize" the low power draw from the LED lights # TLL9RK you purchased from us (thank you!)

expert reply by: Kyle S