TEST FOR STABILITY OF PHOTOMETRIC PERFORMANCE. The tests shall be carried out in a dry and still atmosphere at an ambient temperature of 23 °C ± 5 °C, the complete headlamp being mounted on a base representing the correct installation on the vehicle. 1.1. Clean headlamp The headlamp shall be operated for 12 hours as described in paragraph 1.1.1. and checked as prescribed in paragraph 1.1.2. 1.1.1. Test procedure 1/ The headlamp shall be operated for a period according to the specified time, so that: (a) In the case where only one lighting function (driving or passing beam or front fog lamp) is to be approved, the corresponding light source is lit for the prescribed time; 2/ (b) In the case of a headlamp with a passing beam and one or more driving beams or in case of a headlamp with a passing beam and a front fog lamp: (i) The headlamp shall be subjected to the following cycle until the time specified is reached:
Appears in 2 contracts
Sources: Agreement Concerning the Adoption of Uniform Technical Prescriptions for Wheeled Vehicles, Agreement Concerning the Adoption of Uniform Technical Prescriptions for Wheeled Vehicles