The OBD (On Board Diagnostics) system is an onboard automatic diagnostic system used to monitor a vehicle's emission control system. Although the national standard OBD communication protocol already covers the communication protocol of car manufacturers' OBD, the OBD diagnostic instrument of the testing agency sometimes still cannot read relevant information of the vehicle, such as engine speed, vehicle speed, coolant temperature, fuel pressure, VIN, CAL ID, CVN, etc. This situation may be caused by the following reasons:
Compatibility issues
Different brands of OBD diagnostic instruments may have significant differences in compatibility, adaptability, and depth of data collection for different vehicle models. Due to the inconsistent certification standards of OBD diagnostic instruments on the market, their ability to read vehicle information varies greatly.
Technical updates
With the development of automotive technology, new communication protocols and standards continue to emerge, such as the ISO 27145 protocol, which requires OBD diagnostic instruments to be constantly updated to support new protocols.
Equipment issues
The OBD diagnostic instrument itself may have a malfunction or its version may be too low to support the communication protocol used by the vehicle ECU system.
Vehicle malfunction
The OBD system of the vehicle itself may have problems, such as dust or damage to the interface, low battery voltage, etc., which may cause the OBD diagnostic instrument to be unable to read information properly.
Software version
The OBD system software of the vehicle may be outdated and incompatible with the new OBD diagnostic tool, requiring an update to the OBD system software.
Requirements for detector configuration
The OBD diagnostic instrument configured by the inspection agency should at least meet the OBD communication protocol requirements of GB18285-2018 and GB3847-2018 standards, and should also support reading vehicle engine OBD information of more communication protocols.
Equipment calibration and certification
The release date of the calibration specifications for OBD diagnostic instruments is still far away, which has led to an urgent problem of how to verify the performance of OBD diagnostic instrument equipment in institutions and ensure that data and results meet the requirements of metrological traceability.
Conclusion
Addressing these issues may require testing institutions to update OBD diagnostic equipment, improve equipment compatibility and adaptability, while vehicle manufacturers also need to ensure that the vehicle's OBD system meets national standard requirements. When encountering OBD diagnostic equipment unable to read vehicle information, you can try cleaning the OBD interface, restarting the vehicle, using compatible OBD scanning tools, checking battery voltage, or taking the vehicle to a professional repair shop for inspection and maintenance.
