Troubleshooting LED Clearance Lights On Semi Trailer Flashing Faintly When Using Turn Signals.

Question:

I have rewired a semi trailer with 14ga wire. I have installed all led lights throughout the trailer, and two ground wires. Only when the clearance and the running lights on all the lights will faintly blink when a right or left signal light is turned on. I also have a junction box installed and I have run a much larger jumper directly from the trucks negative on the battery cable and it still blinks.

asked by: Jon

Helpful Expert Reply:

It sounds like there may be an issue with power shorting into the clearance and running lights when you use the turn signals. As LED lights do not require a lot of power it may be the power is jumping the circuits inside your junction box. Be sure to also check for any signs of power shorting inside the trailer connector. Some Dielectric Grease # 11755 should help prevent an issue inside the trailer connector. If your power is shorting inside the junction box you can try some Liquid Electrical Tape # SWC50122 to cover the connectors.

expert reply by: Bud M