Troubleshooting the Brake Light Function of the Optronics Round Trailer Light part # ST40RB

Updated 03/13/2014 | Published 03/12/2014

Question:

The turn signal on the new light isnt working. The light does work but no turn signal. I hooked up the old light and the turn signal works. Both have just 2 wires. Truck is a Chevy silverado 2500 and the horse trailer is an titan avalanche. Any suggestions would be appreciated.

asked by: Mark A

Expert Reply:

The Round Trailer Stop, Turn and Tail Light # ST40RB that you referenced grounds through the mounting hardware. A weak ground could definitely cause the brighter illumination of the # ST40RB to not function. I would make sure that this light is installed on a clean metal surface that touches the frame of your trailer.

If not, you could run a jumper wire from the mounting hardware of the light to the frame of your trailer to improve the light's grounding.

You could also test the assembly by setting it on the negative post of a vehicle battery and then running 12 volts to both wires to see if they both light up differently.

expert reply by: Jameson C