brake light wiring colors

Need to Know what the wire code is for stop lights??

BK---Wh ----GY/BB Which is positive feed? which is Neg? and which is switch

Thanks H
for a 2015 f3-6e6

At what part of the circuit are you asking about?

Based on the 2016 wiring diagram.
From fuse to brake light switch pigtail is red with orange tracer. Pigtail in is red. Pigtail out is black. From pigtail to Brake/Flasher module connector is white. Connector to module is white. Module to left tail light assembly connector is yellow. Module to right tail light connector is green. Both sides connector to brake/turn signal bulb is white.

I wish to install a high intensity brake light. Tap under rear seat next to either brake light on

Then tap into the white wire going to the module.

BRP could never do thins that are universal in the auto industry, sucks.

Is there a ground to the frame or is black neutral??