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Brake switch.JPG
I added a mechanical brake switch to my Mini about 7 years ago and it has worked perfectly every since.
It was a "standard" replacement brake switch from an automotive parts retailer but I can't remember which one. I still have the kinked neck and ringing in the ears from drilling a mounting hole in the pedal bracket frame in situ.
The switch MUST be a "normally closed" switch, so that when the plunger is pushed in (the normal position when the brake pedal is up) the contacts are open; ie the brake lights are OFF. When you push down on the brake pedal the plunger pushes out and the contacts close; turning on the brake lights. (Most push button switches work the other way around. They are "normally open". They are off when the plunger is out, and on when the plunger is in.)
(I used the mechanical switch wired in parallel with the old hydraulic switch to activate a relay to power the brake and high centre brake light on the parcel shelf. This works for me but adds more complexity and wiring leads through the bulkhead.)
Dave D