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Retrofitting a vehicle with daytime running lights (approval mark = RL) is not subject to notification and inspection. It does not require a re-inspection at the road traffic office.

Installation location
The installation location is at the front of the vehicle in the longitudinal direction. The light emitted by the daytime running lights must not disturb the driver either directly or indirectly via the rear-view mirrors and/or other reflective surfaces of the vehicle.daytime running lights
3.2. Height dimensions
a) from the ground to the lower edge of the illuminating surface: min. 25cm
dimmed daytime running lights in use as position lights: min. 35cm
b) from the ground to the upper edge of the illuminating surface: max. 150cm
3.3 Distance between the illuminating surfaces of both daytime running lights
c) for a vehicle width < 130cm: min. 40cm
for a vehicle width ≥ 130cm: min. 60cm
Paragraph <<c>> is not applicable to tractors up to 40 km/h and other vehicles with Vmax up to 30 km/h.
3.4 Side body clearance
d) dimmed daytime running lights in use as position light: max. 40cm
if the light is only used for the daytime running light function, this restriction does not apply.
3.5 Geometric visibility of daytime running lights
- Horizontal angle (to the left and right): min. 20°.
- Vertical angle (upwards and downwards): min. 10°.

3.6 Distance to direction indicators
- more than 40mm
- If the distance is smaller, the adjacent TFL must go out or dim when the direction indicator is activated.

5. homologation mark (approval mark)
- A homologation mark must be affixed to the daytime running lights. The letter "E" and the identification number of the country that has granted the approval are placed in a circle.
- In addition, the daytime running light must bear the mark "RL" for daytime running light.
- If different lights are combined in one headlamp, an approval mark must be visible for each individual light (important for accessories or spare parts).

Examples of approval marks:
Daytime running light = RL
Parking light and marker light = A
Low beam = C, HC, HCR or DC
Main beam = R, HC, HCR or DR
Direction indicator = 1, 1a, 1b