Using caravan external lights when car is unplugged

woodlanewanderers

I would like to be able to turn my caravan lights on when I am moving my caravan on the movers in or out of my drive onto the road in darkness.

I was thinking of using the 12volt socket in the caravan connected via a cable to a 13 pin socket (wired to the side light terminals).  I would then plug a 12 volt plug into the 12 volt socket and pass a lead through the caravan window and plug the 13 pin caravan plug into the socket. Has anyone got any ideas on this.