On Board Diagnostics II: Notes
In parallel with the Low Emission Vehicle program, the ARB developed and mandated OBD II. OBD II as we are aware, requires that all vehicle manufacturers comply with extensive fault monitoring capabilities for all emission related drivetrain control systems.
These systems; DME, AGS and EML must monitor their components electrically and monitor for plausible mechanical engine function. Additionally, OBD II provides a separate Diagnostic Link Connector (DLC) located in the vehicle interior to access OBD II fault codes with an aftermarket scan tool.
BMW center technicians have the advantage of utilizing BMW diagnostic equipment and software (DIS/MoDiC) to interface with all vehicle control systems. However, understanding how OBD II compliance has changed engine mechanical hardware and control system monitoring capabilities should be understood by all BMW center technicians.
All U.S. market BMW vehicles have been OBD II compliant since the 1996 model year.