Using an ATMega328 or any Arduino Uno or the like control the volume of your Android Automotive Radio screen.

Build it with only 3 IC's, U1 and Arduino ( ATMega328), U2 an 74HC14 SCHMITT trigger hex inverter and U3 a CD4066 or 4016 Quad Bi-lateral switch IC.

Visit Youtube

https://www.youtube.com/watch?v=dR6vM4ohU5A&ab_channel=DanielRoss

for Arduino code visit Instructables here.

https://www.instructables.com/Volume-Control-Knob-for-Your-Android-Automotive-To/