Wiring Fog Light on Trailer to Act as Reverse Light and Running Light

Question:

I want to install a fog light that comes on in reverse and also when lights are on and if can wire into aux outlet on trailer connecter

asked by: DANIEL C

Expert Reply:

In order to install a fog light that can be used as both a reverse light and a running light on your trailer, you will just need to have a separate 12 volt power wire running to the light assembly. For proper operation and safety, you will need a switch and diodes, which will prevent back feeding.

I recommend running wire from the 12 volt circuit on the trailer connector back to the reverse/fog lights. You will need to install a switch like # PK34513 in line with the main power wire that is going back to the lights. Diodes like # RM-792 (2-pack) will then be needed at each light you are wiring up.

A diode has 2 inputs and one output and will allow power to only flow one way. You will just need to turn the switch off during normal towing so that the reverse lights will not be on the whole time.

expert reply by: Chris R