The Tune2Air mimics an old iPod classic database structure. iOS requires at least one locally downloaded track inside the native Apple Music app for the car’s system to initialize the connection.
You will need to power the Tune2Air during the update. You can use your car's interface (with the ignition in the "Accessory" or "ON" position) or a specialized 30-pin to USB adapter plugged into a standard wall charger. Step-by-Step Firmware Update Process bovee tune2air firmware update