OBD evolves for ICE and zero-emission propulsion systems

On-board diagnostics (OBD) systems support the protection of the environment against harmful pollutants such as carbon monoxide (CO), nitrogen oxide (NOx), hydrocarbons (HC) and particulate matters (PM) emitted by combustion engines. OBD regulations require passenger cars and light-, medium- and heavy-duty trucks to support a minimum set of diagnostic information to external (off-board) “generic” test equipment.

For the purpose of communication, both the test equipment and the vehicle must support the same communication protocol stack. The communication protocol SAE J1979, also known as ISO 15031, that has been in use for decades will be replaced by SAE J1979-2 for vehicles with combustion engines and by SAE J1979-3 for zero-emission-vehicle (ZEV) propulsion systems.