SAE J1889_202504

This SAE Recommended Practice applies to functions of motor vehicle signaling and marking lighting devices which use light emitting diodes (LEDs) as light sources. This report provides test methods, requirements, and guidelines applicable to the special characteristics of LED lighting devices. This SAE Recommended Practice is in addition to those required for devices designed with incandescent light sources. This report is intended to be a guide to standard practice and is subject to change to reflect additional experience and technical advances. The 2019 version allowed for flashing functions to be photometrically stabilized and measured while flashing. In this update, any dual usage LED function, where the flashing function is also used as a steady operating function, the flashing function shall be stabilized and photometrically measured with the LEDs in steady operating mode. To be harmonized with ECE, a third method to determine photometric values will be added. The three methods will be: 1 Wait 30 minutes and record photometry. 2 Real time monitor stability for 1% change over 5 minutes and record photometry. 3 Pre-determine ratio at 30 minutes and use with data taken at photometric stability. Changed sections in the document: 5.5.2: Testing of flashing functions 5.5.4: New method that allows photometric stability to be monitored on goniometer 5.6: Color test references SAE J578 Changes to definitions: Definition 3.1 changed wording from “minimum” ratio to “final” ratio and subsequent wording changed throughout the document. Definition 3.3 changed wording from “maximum” ratio to “initial” ratio and subsequent wording changed throughout the document.