Where is the optical fiber?
Some BMW car types with Optical fiber Amplifier, the sound work via optical fiber cable (from the factory radio head unit to speaker), please take a look the photo showed as below:
Why need to move the optical fiber to our power cable?
When installing our android screen, you need to connect our power cable (female connector) to the factory radio head unit (instead of factory power harness). If you don't move the optical fiber to our female connector, then the optical fiber will not work, it will no sound output.
The below photo is a female connector of our power cable, it will connect to the factory radio head unit, it has 4 holes that are ready for optical fiber cable.
How to move the optical fiber to new power cable?
Wire diagram
Video demo