Why can’t obd communicate after connecting？

When you encounter the problem that you can’t communicate after OBD connection, you can try the following steps to solve it:

1. CheckHas OBD diagnostic instrument been upgraded to the latest version?.

2. Check whether the data line of OBD diagnostic instrument is open, especially7 jiao.

3. Check the OBD interface of the vehicle for physical damage or poor interface protection, such as mud and dust on the interface or unreliable pin connection.

4. Check whether there is an open circuit between the OBD connection port of the vehicle and the ECU connection line.

5. Check whether the connection of OBD interface meets the national standard. The 9 of the K line is connected to the 7, and the CAN line needs to be on the 6 and 14 feet (for example, Haowo, 12-year Geely Free Ship, 13-year Geely Global Hawk, etc.).

6. Some models have two 16-port connectors. Please ensure that the connectors are plugged in (for example, Haowo, Chang ‘an school bus, Jinbei Sea Lion refrigerated truck, etc.).

7. The OBD connection port of some models is not 16 ports or 9 ports, and other types of connection ports are used.

8. If the connection with ECU is unstable or easy to crash, it is recommended to restart the vehicle and try several times. For example, when reading vehicle CVN information, if the diagnostic instrument crashes, you can first remove the OBD diagnostic instrument, turn off the vehicle key, and then restart it.

9. The vehicle ECU has a protection function, so you can go to the 4S shop to activate it. Drive back without turning off the engine (such as Zhonghua and Chang ‘an).

10. The vehicle’s EPS, ABS and power steering module may interfere with the vehicle’s communication (for example, Futian, Chang ‘an, Yingzhi, etc.), so you can disconnect the ABS insurance, EPS controller or 6 and 14 communication pins.

11. Change one-button start to key start (for example, China).

12. Check whether the vehicle has been modified.

13, check whether the pin is short, contact is good.

14 and 16 pins need to be connected with a 12V power supply or the communication pin voltage is too low and particularly unstable.

15. Remove magnets or other electromagnetic interference sources that may interfere with communication inside or outside the car.

16. If there are too many unfinished items in the ready state and it is impossible to get ready through full driving.

17. Check whether there are fault codes reserved by the manufacturer or the manufacturer has put the historical fault codes in the fault code confirmation area.

18. Check whether the speed data and speed data returned by the vehicle are correct (for example, Futian, Panther, Jianghuai, etc.).

19. Check whether the data flow is accurate and stable and whether the data volume is sufficient.

20. Check whether the aftertreatment uses the same ID as the engine.

21. Try to upgrade ECU of vehicles (such as Volkswagen, Wuling, Huaichai, Cheng Liwei, Chery and Changan Benben).

22. For some vehicles, there may be no solution, such as Huatai Santa Fe (list of vehicles with unsuccessful communication).