Can Trailer Running Lights be Powered Off of a Battery When Not Connected to a Trailer

Question:

I would like to run my Airstreams running lights from the trailers battery when not hooked up to the tow vehicle. How would you suggest doing this?

asked by: Mike H

Expert Reply:

I do have a way that you can wire the lights on the trailer so that they will come on when connected to the tow vehicle or off of a battery on the trailer.

What you will need to do is add 2 diodes, # RM-792, to the wiring set up. You will also need a switch, # D16740, and a wiring installation kit # 55151.

I have included a diagram of how this should all be wired. Basically the wiring to the light will come from 2 sources; the trailer connector, and the battery via a switch. The diode prevents backfeeding.

The colors used are just to show contrast. Make sure the switch is turned off when the trailer is connected or the lights will run all the time and can get too much power sent to them.

expert reply by: Michael H