Originally Posted by chxf

As by low, in Europe every car must be equipped with a rear fog lamp. Either on both sides of the car or on that side where the driver is (the end of the car in the corresponding driving direction).
That's why our EU-Crossfires has different tail lamps. One with the back up light (white) and one with the fog light (red).

The light **** has two additional position when light is on (position or low beam). First pull engages the front fog lamps. Second pull activates additionally the rear fog lamp. It's not possible to light the rear fog lamp only.