I'm looking for a wiring diagram that will allow my under seat LED lights to turn on when the car door opens, or with a switch.

I am planning on tapping into an existing light that goes on when the doors open, but I am not sure how to write a switch that will allow me to keep the lights on when the doors are closed.


1 Answer 1


You'll need a double-throw switch, i.e. one that can switch one output to either of two inputs. I'd get one with an off position as well (often labelled on-off-on in shops).

Before wiring it up, you'll need to check your car's wiring diagram to see how the existing interior lights are wired - you'll need to do yours the same way. It will depend if the switch is on the feed side or the ground side.

If the switch is on the feed side, connect as follows :

12v - fuse - switch 1
Door switch - switch 2
Switch common - lights - ground

If it's the other way round, connect it like this:

12v - fuse - lights - switch common
Switch 1 - ground
Switch 2 - door switch
  • clear and concise - excellent.
    – Solar Mike
    Commented Jun 24, 2018 at 8:48

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .