ISO 15031-5 ISO DIS 15031-5.4:2004 Road vehicles — Communication between vehicle and external equipment for emissions related diagnostics — Part 5: Emissions-related diagnostic services. ISO 15031-6 ISO DIS 15031-6.4:2004 Road vehicles — Communication between vehicle and external equipment for emissions related diagnostics — Part 6: Diagnostic trouble code definitions. SAE J2012 SAE J2012: Diagnostic Trouble Code Definitions Equivalent to ISO/DIS 15031-6, April 30, 2002. ISO 15031-7 ISO 15031-7:2001 Road vehicles — Communication between vehicle and external equipment for emissions related diagnostics — Part 7: Data link security. SAE J2186 SAE J2186: E/E Data Link Security, dated October 1996. ISO 15765-4