Solutions:
1. Try to reset the car Bluetooth system. (usually there is a manual)
2. Restore factory Settings after the backup of data.
3. Replace other mobile phones and try to connect, and determine whether it is the fault of vehicle-mounted Bluetooth.
4. If there is no sound, please first adjust the Bluetooth volume from the phone or the car.(If it is still silent, considering whether the car Bluetooth has been used for too long and will cause aging phenomenon or whether the wiring of the car Bluetooth connection speaker is loose, it is suggested to check it in the car store)
5. At present, there are various kinds of car Bluetooth, with different performance. Some car models are equipped with vehicle-mounted Bluetooth, while some car models without such Bluetooth may need to install vehicle-mounted Bluetooth.
6. If the mobile phone still fails to connect to the vehicle-mounted Bluetooth after normal troubleshooting, there is a great possibility that the problem may be caused by the vehicle-mounted Bluetooth device.
