My 91 Bluebird TC2000 had
a pressure type switch that was mounted inline with one of the brake lines. Pressure from the brake fluid activated the switch and turned the brake lights on.
I had an issue with it last summer and it shorted out causing the brake lights to stay on all the time, which caused the back-up brake booster to run all the time, which caused the switch to over heat and leak.
I had to replace it with an updated, plunger type switch which is mounted near the brake pedal and activates when you step on the pedal. You can read about that adventure here...
http://www.skoolie.net/forum/viewtopic. ... highlight=