Combining Brake Light and Turn Signal Circuits on a Freightliner Dump Truck Trailer Connector

Updated 06/11/2018 | Published 06/09/2018

Question:

I am trying to wire my stop and turn on the same element. Currently signal blinks as long as the brake is not applied. Once the brakes are on then the signal is constant. Will this HM48925 relay separate the function so it will be intermittent when signal is on? Also, my tail or running lights are fine, can I just wire the white ground wire and leave the running lights as they are? I could not find this in your FAQs as this is on a an air brake equipment trailer behind a Freightliner dump truck. It has 7 pin round connector.

asked by: Michael W

Helpful Expert Reply:

If you are wanting to combine the brake light and turn signal circuits on the tow vehicle side trailer connector you can pretty much use any converter for that including # HM48925. On the input side the green wire will go to the right turn signal, yellow goes to the left turn signal, and red goes to the brake light circuit. If you do not need to wire in the brown wire for the running lights, since yours are working properly, you can ground that brown wire with the white wire.

On the output side you will have green for right turn and brake lights, yellow for left turn and brake lights, white is the ground, and brown won't do anything.

expert reply by: Michael H