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My car has 2 USB sockets that provide power and also serve as a data link for audio, etc. from phones to the entertainment system. The entertainment system also accepts a Bluetooth connection for hands free and audio, etc.
The audio connection via USB provides more features than the connection via Bluetooth, for example album art is displayed on the entertainment system and I can seek to a specific point in a track.
The downside of using the USB connection for data is that i must also use it for charging and it doesn’t provide much current.
I also have a 12v to USB adaptor in the car that provides 2.1A and charges the phone much more effectively.
My question is; is it safe make my own wiring to take power from the 12v to USB adaptor and data from the car’s sockets so that I can get the advantages of 2.1A charging and the data connection to the entertainment system?