HJ 1237-2021 in English

HJ 1237-2021 is a mandatory standard in the field of motor vehicle emission inspection in my country. It systematically regulates the technical requirements and operating procedures of inspection institutions for the first time. After the implementation of the standard, it will directly affect the operating mode of 38,000 motor vehicle inspection institutions across the country.

Hybrid vehicle inspection

For plug-in hybrid models, the standard clearly requires: when the power> 80% should be discharged on the road first, and the pure electric mode data during the inspection is recorded as zero. After a certain inspection station adopted the forced discharge mode of the chassis dynamometer, the engine start success rate increased to 92%.

OBD communication failure processing

Establish a "comparison of 5 units of the same model" mechanism: if 3 consecutive communication failures occur, the centralized reporting procedure for exceeding the standard model needs to be initiated. A Beijing institution discovered a design defect in the protective cover of the OBD interface of a certain brand of vehicle through this mechanism.

• Video Monitoring: 2 high-definition cameras shall be installed diagonally on the detection line, with a storage period of ≥6 months
• Standard Materials: The validity period of standard gas is shortened to 3 months, and the efficiency of the converter is verified monthly
• Personnel Management: The report approver shall be authorized in writing by the legal representative

Compared with GB 18285-2018, this standard adds:

1. OBD actual monitoring frequency (IUPR) data recording requirements
2. Remote emission terminal networking verification of heavy vehicles
3. Technical parameter specifications for video monitoring devices

It marks the transformation of emission supervision from terminal detection to whole process control.