HJ 437-2008 in English

本标准规定了装用压燃式发动机汽车及其压燃式发动机、装用以天然气（NG）或液化石油气（LPG）作为燃料的点燃式发动机汽车及其点燃式发动机的车载诊断（OBD）系统技术要求及试验方法。
本标准适用于设计车速大于25km/h的M2、M3、N1、N2和N3类总质量大于3500kg的M1类机动车装用的压燃式（含气体燃料点燃式）发动机及其车辆的OBD系统的型式核准和生产一致性检查。

Scope

This standard specifies the on-board diagnostic (OBD) system technology for vehicles equipped with compression ignition engines and their compression ignition engines, and vehicles equipped with ignition engines using natural gas (NG) or liquefied petroleum gas (LPG) as fuel and their ignition engines. requirements and test methods. This standard is applicable to compression ignition (including gas fuel ignition) engines installed on M, M, N, N and N categories of motor vehicles with a design speed greater than 25km/h and M category motor vehicles with a total mass greater than 3500kg and their OBD systems. Type approval and production consistency inspection. If N and M category vehicles equipped with compression ignition (including gas fuel ignition) engines have carried out OBD system type in accordance with the provisions of GB 18352.3-2005 Light Vehicle Pollutant Emission Limits and Measurement Methods (China Phase III and IV) If the engine is approved, its engine may not be subject to type approval according to this standard.