Quote:
Originally Posted by Qsilver7
A fast blinking turn signal usually indicates that one of the bulbs is blown. The blown bulb causes a change in resistance...so the indicator blinks faster than normal.
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Old school thermal flasher devices used the total electrical load (current, in amps) to control the flash rate, via a heated element. Once a signal bulb blew, the electrical load changed and therefore so did the flash rate. This response has become known as an indication of a failed signal bulb but I suspect it was a happy coincidence and not intentional.
Roll forward to today's modern LCM-III controlled signal lamps and a flash rate change (on the cluster indicator only) to indicate a failed signal bulb is simply the modern incarnation of what car owners/drivers have experienced for many years and expect to see. The LCM is well "aware" of the failed lamp via hot and cold monitoring, which is in effect measuring the electrical load, kinda like the old thermal flasher circuit, and could just as easily start whistling Dixie or any other form of alert function. Rapid flashing is what drivers expect so that's what they get. But only on the cluster - unlike the old thermal flashers that actually flashed the signal lamps faster too.
And I love that we still get the "tick tack" sound when the signals are on. Same deal - had it for years (with mechanical contacts opening and closing) so we would miss it with modern electronics. I guess it also reminds us we have signals operating too.
