§ 49a StVZO
(1) Motor vehicles and their trailers may only be fitted with the prescribed and authorised lighting equipment. Luminous materials and retro-reflective devices are also deemed to be lighting equipment. The lighting equipment must be installed in accordance with the regulations and must be permanently operational. Lighting equipment on motor vehicles and trailers covered by Council Directive 76/756/EEC of 27 July 1976 on the approximation of the laws of the Member States relating to the installation of lighting and light-signalling devices on motor vehicles and their trailers (OJ L 262, 27.9.1976, p. 1), as last amended by Directive 2008/89/EC (OJ L 257, 24.9.2008, p. 14). 2008, p. 14), must comply with the technical requirements of paragraphs 2, 5 and 6 and Annexes 3 to 11 of ECE Regulation No. 48 of the United Nations Economic Commission for Europe (UN/ECE) - Uniform provisions concerning the approval of vehicles with regard to the installation of lighting and light-signalling devices (OJ L 323, 6.12.2011, p. 46).
(2) Headlamps may be covered or retractable if this does not impair their permanent operational readiness.
(3) Lighting equipment must be designed and installed in such a way that they do not impair each other's effect more than is unavoidable, even if they are combined in one device.
(4) If lighting devices of the same type are installed in pairs, they must be installed at the same height above the road surface and symmetrically to the longitudinal centre plane of the vehicle (determined by the external geometric shape and not by the edge of their illuminating surface), except in the case of vehicles with an asymmetrical external shape and motorbikes with sidecars. They must be of the same colour, of the same intensity and - with the exception of parking lamps and direction indicators - must be lit simultaneously. The regulations on the height of the lighting equipment above the carriageway apply to the unladen vehicle.
(5) All forward-facing lighting equipment may only be switched on together with the rear lights and the lighting equipment for registration plates or transparent registration plates. This does not apply to
- Parking lights,
- direction indicators,
- the display of illuminated signs (Section 16 (1) of the Road Traffic Regulations),
- work lights on
- a) agricultural or forestry tractors,
- b) agricultural or forestry machinery and
- c) motor vehicles of the military police, the federal and state police, the Federal Criminal Police Office and the customs investigation service,
- daytime running lights that comply with the provisions set out in the Annex to this regulation.
(6) Only light sources intended for this purpose according to their design may be used in headlamps and lamps.
(7) Luminous materials and retro-reflective materials may be used for prescribed or authorised warning paints, warning signs and the like on motor vehicles and trailers.
(8) For all headlights and signalling lights fitted to the motor vehicle or train, an adequate electrical power supply must be ensured at all times under all normal operating conditions.
(9) Tail lights, rear fog lights, lane departure lights, clearance lights, stop lights, rear direction indicators, rear amber non-triangular side reflectors and reflective means, rear side marker lights, reversing lights and licence plates with lighting devices as well as two additional triangular reflectors - for trailers according to § 53 paragraph 7 two additional reflectors as prescribed for motor vehicles - may be mounted on a removable plate or frame (light carrier):
- trailers in agricultural or forestry operations,
- trailers for the transport of railway wagons on the road (road scooters),
- trailers for the transport of boats,
- tower cranes,
- conveyor belts and goods lifts,
- Towing axles,
- towed vehicles,
- chassis that are transferred for the purpose of attaching the superstructure,
- mobile construction huts,
- caravans and pack wagons in the showman's trade in accordance with Section 3 (2) sentence 1 number 2 letter b of the Vehicle Licensing Ordinance,
- trailed implements for road maintenance,
- trailers for transporting long materials.
- The lamp holder must be mounted at right angles to the carriageway and to the longitudinal centre plane of the vehicle; it must not be able to swing.
(9a) Additional reversing lights (§ 52a paragraph 2), tail lights (§ 53 paragraph 1), stop lights (§ 53 paragraph 2), reflectors (§ 53 paragraph 4), rear fog lights (§ 53d paragraph 2) and direction indicators (§ 54 paragraph 1) shall be permanently installed on vehicles or load carriers in the same number and type as the corresponding prescribed lighting equipment if load carriers or loads carried project even partially into the angles of the existing prescribed lights on the motor vehicle or trailer as required in paragraph 1 sentence 4. The electrical switching of the rear fog lights must be designed in such a way that the rear fog lights on the vehicle are switched off. The rear fog lamps must be switched off and on again automatically by plugging in or unplugging the plug for the additional rear fog lamps.
(10) In the case of the trailers referred to in paragraph 9 number 1 and § 53 paragraph 7 and the attachments referred to in § 53b paragraph 4, the light carrier may consist of two or - in the cases of § 53 paragraph 5 - three units if these units and the brackets on the vehicles are designed in such a way that improper attachment is not possible. Front position lamps may also be fitted to these units.
(11) The definitions of 'illuminating surface', 'light-emitting surface' and 'angle of geometric visibility' in Annex I to Directive 76/756/EEC apply.
Source: Quelle: https://www.gesetze-im-internet.de/stvzo_2012/__49a.html (translated)