How to connect the car radio to the mobile phone to listen to music: 1. There is an AUX interface on the car radio. This is the audio auxiliary interface. In layman's terms, it means that the external signal is connected to the radio and used as an external amplifier through the car audio. If you have an AUX interface, buy a cable like the one below and plug it into the headphone port of your phone and plug it into the radio interface to listen. 2. The car radio with Bluetooth function can be paired with your mobile phone. The method is the same as pairing a mobile phone with a Bluetooth headset. Once Bluetooth is discovered and matched, you can listen; 3. Buy a player like the one below, plug it into the cigarette lighter, and then Bluetooth match the music in the phone to transmit FM broadcasts through it, and then tune the radio to that frequency. For example, if you adjust the player to FM100 and the radio to FM100, you can listen to the music on your mobile phone.