Audi of America, which offers LED daytime running lights on all its models, says that the LEDs turn off when a turn signal activates because federal regulations say that no lights that are brighter than the turn signals can be on at the same time during daylight hours, which could prevent other drivers and pedestrians from noticing that a turn signal is on.

Led headlights

Among the advantages of LEDs are that they emit more light per watt, they use less energy than other types of lights and they generate a bright, distinctive light. Federal safety regulators apparently believed that LEDs can overpower the light cast by amber-colored turn signals.

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Answered by Rick Popely on October 31, 2012 in I'm Just Wondering | Permalink

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