This SAE Recommended Practice provides the lighting function identification codes for use on all passenger vehicles, trucks, trailers, motorcycles, and emergency vehicles.
Update §2.1.2 - References to federal publications have been updated
Revised Table 1 Title and content to include:
The additional lighting code delineator “X” for AFL functions is intended to be used once in the lighting code marking. Not all the AFL codes might be used for a specific marking application and there is no specified order of hierarchy for the AFL codes. There is also no specified order of location of the AFL codes listed within a lighting code lamp marking. The letter “X” is currently used as an AFL type lamp and this change is an extension of the current code X usage.
An example of such an AFL code: X CERV