This proposal concerns lamps equipped with several light sources and fitted with an operating tell-tale that indicates the failure of any one of these light sources. The current provisions for the failure of one light source (the “N-1” requirement) are difficult to apply as a complete photometric check for all possible combinations of light source failure is required. The revised text follows the approach of supplement 17 to Regulation No. 87 and removes the requirement to check the complete photometric requirement, in case of failure of any light source, when the lamp is fitted on the vehicle with an operating tell-tale.
24. The expert of GTB introduced ECE/TRANS/WP.29/GRE/2015/8 with a proposal to update the provisions relating to failure of light sources when an operating tell-tale is installed. GRE noted that this document was part of collective amendments to various Regulations (ECE/TRANS/WP.29/GRE/2015/10, ECE/TRANS/WP.29/GRE/2015/11, ECE/TRANS/WP.29/GRE/2015/12, ECE/TRANS/WP.29/GRE/2015/14, ECE/TRANS/ WP.29/GRE/2015/18). Following comments from the experts of Germany and the Netherlands, GRE requested GTB to revise the proposal and submit a new document to the next session.