I have a Bluetooth radio on my car but the volume wheel is broken. I am wondering if there's a way to make my Android act as a remote control for the radio, allowing me to increase its volume. I don't want to play music from my phone, only control its volume.
It depends. Usualy when you would pair a device to you car audio player, the player would only want the files on it. But that depends on the player and what type of connection it makes with it's paired devices. So basicaly I think you will have to try and see if it works.