What Makes Turn Signals Click Like That?
This video answers the turn signal question you never knew you wanted to ask.
Somewhere in the commandments of car ownership, it’s written in stone that for a turn signal to work properly, it must click. There’s no getting around it. It’s a feature that has saved the lives of many a driving school instructor. Okay, so maybe the extra brake pedal on the passenger’s side is better for that, but still.
Anyway, what the heck is it that makes that distinct little noise that everybody (but BMW owners) knows so well?
Anatomy of a Blinker
The folks at Jalopnik were just as curious as you are, so they set out on a quest to find the click, and what causes that sound. They actually dissected the blinker systems from two separate vehicles, and made the video above about it.
Blinker One: Jeep
The first blinker to fall victim to the Dremel comes from a Jeep that appears to have recently completed a mud-bogging mission. The Jeep is conveniently devoid of interior paneling, and that makes it easy to locate the small blinker unit near the driver’s side footwell.
Turns out the unit works by heating a bi-metallic spring. When the spring bends, it contacts another piece of metal in the blinker unit, which completes a circuit.
Blinker Two: VW Bug
For a second example, Jason Torchinsky uses the blinker unit from his Volkswagen, which is much simpler. In this design, an integrated circuit controls a tiny metal relay that is barely visibly moving, though it does in fact move to produce the blinker’s signature sound.
Modern Cars
Of course, many modern cars do use a small speaker to convey the fact that your blinker is on, as you might have guessed. But it’s still fascinating to see how we did it before computer technology!