Can Clearance Lights be Installed on Side of Trailer as Additional Turn Signals

Question:

I have a 40 ft. 5th wheel trailer that I would like to add some auxiliary turn signals along the side of....I am looking at placing an Optronics STL78RB at the very rear still on the side of the trailer and an Optronics STL78AB at the mid-way point and the front of the trailer.....is this something that can be done? I would only like the lights to come on when the turn signals are activated......

asked by: Shaun P

Expert Reply:

The DOT rules are typically that if the turn signal is facing the side of the trailer it needs to be amber in color like the part # STL78AB and then if facing the rear it can be amber or red like part # STL78RB. However, if the light also carries the stop light circuit it would have to be red.

You would need to check with your local DOT to confirm this, but in the meantime I attached a help article on trailer lighting options as well.

To do what you are looking to do would require you convert your trailer taillight circuits from combined to separate so that you can isolate the blinkers from the brake lights. This will allow the aux lights you want to install to blink separately from the brake lights. To do this you will need to use a signal converter like part # 118158 to tap into the trailer wires. Once you have the blinkers separated from the brake lights you will be able to wire them to either of the lights mentioned.

expert reply by: Jameson C