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Beware of the Dangers of Automatic Car Lights

View profile for Michael Pace
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No doubt like me whilst driving home from work in the dark you have come across cars that have no rear lights illuminated, yet their headlights appear to be on. This is a danger created by cars which are fitted with automatic lights.

The same cars are fitted with 'driving lights' or 'daytime lights', which are on during daylight hours and are designed as a road safety feature to help us spot oncoming cars. Some motorcycles also have these.

Cars fitted with automatic lights will, when the light switch is on 'auto', switch on all the lights when the car senses that daylight is diminished.
That same light sensor will also cause the instrument panel to light up when the switch is not in the auto position, leading you to believe as you set off in the dark that you have you lights on, when in fact only the front daytime lights are on. Your eyes also are tricked because most daytime lights are bright enough to see lighting up the road while driving along a street lit road. Your rear lights though will not be on.

Clearly this is a design fault which manufacturers need to get on top of quickly before we start to see more rear end shunts in not lit areas.
It seems to me that the only way to make sure you do have your lights on, is to leave the light switch in the auto position. That way you will always have your rear lights on when driving in dim light. 

This however leads to another problem because to switch your fog lights on you have to turn the switch to the headlights on position to switch on your fog lights. Then, when turning off your lights at the end of the journey, you must remember to turn them to auto and not to the off position!