These circuits were originally designed to monitor two 21 W brake lights, but could be used to monitor a wide variety of bulbs. The monitoring depends on the potential difference across a resistor. With a total brake light power of 42 W, the p.d. is 0.77 V which will drop to 0.385 V with one bulb extinguished.
Car brake light failure indicator
Anzeige fuer Bremslichtausfall beim Automobil
Practical Electronics ; 14 , 7 ; 521
1978
1 Seite
Aufsatz (Zeitschrift)
Englisch
KRAFTFAHRZEUG , BREMSVORGANG , LAMPE , WARNGERAET , AUSFALL