Autumn fog in the taxi: Safe on the road with the right lights.

While others are still sleeping, many taxis are already on the road. Early trips to the train station, medical transports at dawn, or the last shift after midnight: In autumn taxi and rental-car drivers encounter fog and poor visibility particularly often. That makes functioning lighting all the more important. But even modern vehicles with automatic lighting are not always sufficiently prepared.

“Light sensors react to brightness. During the day, fog is often bright enough that the automatic system does not switch to low beam,” explains Christopher Lang, automotive expert at ATU.

Whoever relies solely on daytime running lights will often drive with no rear lighting and with insufficient visibility ahead. Especially in everyday taxi operations, when passengers must be picked up on time and the vehicle is in service for many hours, the lighting should therefore be regularly checked. In fog, rain or snow, it is advisable to manually switch on the low beams if the automatic mode does not respond. High beams are unsuitable in dense fog: They reflect off the water droplets and dazzle the driver further.

Fog lights may be switched on when fog, snowfall or rain significantly impair visibility. They illuminate the roadway broadly and improve visibility near the ground. For the rear fog light, stricter rules apply: It is allowed exclusively in fog and with a visibility of less than 50 meters. On the motorway, this distance can be estimated using the guide posts. With visibility below 50 meters, a maximum speed of 50 km/h also applies—even on the motorway.