Automotive lighting#Rear fog lamps

A rear fog lamp is a rear fitted to a vehicle, especially bright red auxiliary lamp. Compared to conventional tail lights it emits 40 times stronger. It is used to make the vehicle more visible in poor visibility. Rear fog lights must either symmetrically in pairs, or individually, in the center of the vehicle or the left, are attached.

Basics

In Germany 1991 erstzugelassene cars must be equipped with a top speed over 60 km / h and its supporters with one or two rear fog lights since January 1. Other motor vehicles (eg tractors, motorcycles) and trailers under 60 km / h must be fitted with a rear fog light. In a retrofit old vehicles is not required. With imports of cars from countries where normally no rear fog light is installed, a retrofit as part of a so-called homologation is required.

Use the rear fog lamp

The rear fog lamp is an instrument of active safety. Since she can dazzle the driver behind strong because of their brightness, their operation is limited by strict rules, however, which vary by country.

According to (§ 17 Highway Code ) of the German Road Traffic Regulations ( Highway Code ) may fog lights are only used when the visibility due to fog less than 50 m ( § 17 paragraph 3, sentence 5 Highway Code ). This is in Germany the distance between the guide posts at the edge of roads and highways in a straight route, which they are capable to determine the visibility. The visual obstruction can not be caused by rain or snow.

In ( § 3 Highway Code ), there is also the following provision to the maximum speed in fog: when the visibility is limited by fog less than 50 m (the same condition as for the use of the fog light ), may speed max. 50 km / h amount. Therefore, with proper use of the fog light a maximum speed of 50 km / h is allowed.

An indicator lamp with yellow light on the dashboard is required. Nevertheless, it is often observed in practice, that driver after driving through a foggy place forget to turn off the rear fog lamp. If, by misuse in a hazard to other road users or even an accident, the caution money is 15 or 35 euros.

In other countries, different rules may apply for use: In Belgium, the rear fog lamp must, for example, at a visibility below 100 meters, will be conditionally turned on by fog, snow or rain. In France, it must be turned on in fog and snow entirely without sight distance limitations, but not in rain, during the operation of the rear fog lamp is entirely prohibited in Slovakia.

In a train (vehicle with trailer (s ) ) only need the rear fog lights on the last trailer to shine. This not only saves power, on the other hand, reducing the glare that would generate strong rear fog light of the towing vehicle by reflections on the trailer. Turning off the fog lights on the towing vehicle or on the first trailer is only permitted if the respective decrease or reconnection takes place automatically by plugging or unplugging the plug for the trailer lights.

According to ECE R48, the rear fog light of the towing vehicle must be switched off during operation of a trailer. For cultivation of charge carriers (eg bike carriers ) with lighting units must be switched off to reduce glare. The automatic off and on again on the towing vehicle is realized by

• A mechanical zero return in the socket or by a so-called micro-switches,
• An additional cut-off relay,
• The control device upon detection of the trailer ( automatic)