Ah, not that I want to be picky but some flashers use relays also. Mostly
the ones marked "Electronic"

"JeffM" wrote in message
om...
Car blinkers have thermal interrupters:
the more current they pull, the faster they blink.
Left blinker faster than the right?
Probably a burned out bulb.

Intermittent windshield wipers do use a relay.
A variable-period / constant on-time timer drives it.