The reason the fog lights are on with the low beams and off when the high beams are on is because you are supposed to use them when it is foggy and when it is foggy it is actually harder to see using high beams because the light reflects off of the fog and all you do is light up the fog, not the road.

If you don't believe me try it next time you are out in the fog, turn on the high beams and see how hard it is to see the road. Believe it or not, the people who designed the car actually did it right...you use the fog lights with low beams and keep your high beams OFF in the fog...and when it is not foggy shut the fog lights off and use your low beams.

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz