You learn something new from the Internet every day…

I always thought floor-mounted dimmer switches disappeared from cars due to the advent of low-cost relays that made it easy to mount a low-amperage switch on the stalk of the steering wheel. There is some truth to that — but if that was the case, floor-mounted dimmer switches would have disappeared in the early 1960s.

Another theory could say the federal government banned floor mounted dimmer switches as a safety issue but it turns out that’s not the case. There is no regulation prohibiting floor mounted switches. An automaker could make a car with floor mounted dimmer switches if the so choose nowadays. You could argue that floor mounted switches are safer, especially if your trying to encourage drivers to keep their hands on the steering wheel at all times.

It turns out the real reason was with smaller front-wheel drive cars, the foot-wells in cars became narrower, and there simply wasn’t room to safely put the switch. When front-wheel drive cars became common, there simply wasn’t room for the dimmer switch between the brake, gas pedal, clutch and/or emergency brake. When front-wheel drive cars became common, with stalk mounted dimmers, automakers decided to phase out — over time — the floor dimmers on even large cars with plenty of room for floor dimmers in the name of standardization and reduced driver confusion.