What failure is indicated by a rapidly flashing turn signal?
Show the correct answer
Correct answer
C. Burnt-out turn signal bulb.
Explanation
The photo shows a car's rear lamp with the orange indicator switched on. A fast-flashing indicator signals a burnt-out indicator bulb - answer C. Neither a weak battery (A) nor a short circuit in the high-voltage leads (B) changes the flashing frequency.
The Regulation on the technical conditions of vehicles requires indicators to flash at a frequency of 90 cycles per minute with a permitted deviation of 30, and the vehicle to have a warning signal showing that the indicators are working; if any indicator is faulty, this signal should not light up, should stay on continuously or should flash at a clearly changed frequency. Manufacturers most often choose the last option: the relay or control unit detects that one bulb is missing in the circuit and doubles the flashing rate, so that you notice the fault without getting out of the car. A weak battery shows itself through difficult starting and dimming lights, and high-voltage leads supply the spark plugs and have nothing to do with the indicators. When the arrow on the dashboard flashes twice as fast as usual, you walk around the car, check which indicator is not lit and replace the bulb - driving with a faulty indicator is a petty offence and a real risk, because nobody knows you are turning.
Legal basis: Annex No. 6 to the Regulation on the technical conditions of vehicles and the scope of their necessary equipment