Hector Fratty

(In compliance with SAE International’s intellectual property policies, this report is rather general in nature and there can be no reference to specific statements by particular participants –ed.)

Recently SAE International’s (formerly the Society of Automotive Engineers) Lighting Systems Group held their Spring meeting at Savannah, Georgia. Technical sessions were held to check in on progress updating SAE’s various lighting-related technical standards; a notable bit of progress was the adopted proposal to add new categories to J914, the SAE technical standard for side turn signals.

The list now includes body-mounted side turn signals more or less in accord with UN Regulation 6 Category 5, body-mounted side turn signals not in accord with UN R6 Cat 5, mirror-mounted side-facing side turn signals, and mirror-mounted rear-facing side turn signals. A different range of angles and intensities is specified for each, and the mirror-mounted rear-facing side turn signals may emit red or yellow light (all others must emit yellow light). An interesting point in the discussion included the relative merits and drawbacks of nominating certain kinds of signals as “mirror mounted” when future vehicles may not have side-view mirrors as we know them today (perhaps they will have cameras instead, for example). There was considerable discussion of why the SAE standard which carries no regulatory force and is relevant only in North America where the side turn signal function is optional needs five types of side turn signal when the UN Regulation applicable in large swaths of the world where the side turn signal function is mandatory gets by with just two types (Categories 5 and 6).

Another pointed discussion took place during the session of the Rear Lamp Modernisation and Rationalisation Task Force; the presentation was primarily focused on deleting red as an allowable colour for rear turn signals, but this idea did not meet with much enthusiasm. There was greater receptivity to the idea of removing the uniquely American “EPLLA” (Effective Projected Luminous Lens Area) requirements which mandate 50 cm² of lit lens area for the stop light and rear turn signal functions on vehicles less than 2.032 m wide and 75 cm² for vehicles therewider; it is felt that these EPLLA requirements are a design constraint without a safety benefit. It is certainly true that the EPLLA requirements often require global automakers to choose between redesigning a rear lamp cluster just for the American market or simply flashing the red stop lamps to provide the turn signal instead of using yellow rear turn signals considered adequate outside North America.