There are generally two reasons for this:
1, the capacity of the U disk has exceeded the capacity that the vehicle can read, resulting in the vehicle can not detect the U disk. If the owner uses a small brand or mini U disk, it may be because the main controller performance of this U disk is relatively poor, and the vehicle is difficult to detect the U disk.
2, the U disk itself has problems. The vehicle system has no way to recognize the NTFS format, and some vehicles can't even recognize the FAT32 format. Insert the U disk into the computer to see what format is, if the format is wrong, you can convert it to fat format on the computer.