A closer look
Turn signal clicking sounds used to be the literal noise of a thermal relay mechanism heating up and snapping back into place. Older cars used a bimetallic spring that would bend as electricity flowed through it, breaking the circuit, cooling down, and snapping back to complete the circuit again, producing that rhythmic clicking noise. Modern vehicles use entirely digital computers to flash the lights silently, but car manufacturers deliberately pipe an artificial clicking sound through the dashboard speakers. They do this because drivers got so used to the auditory feedback that they would forget to turn their blinkers off without it, proving that we are all just Pavlovian dogs conditioned to respond to meaningless synthesized dashboard noises
