Typical error - USB not compatible with iphone
It's all in the title: contrary to what is stated in the description, the car radio is not iphone compatible via USB.
You have to connect via Bluetooth. But it's a pain because the connection isn't made automatically, so you have to redo the operation on your phone every time you switch the car radio on and off.
Disappointed as it was precisely for this (supposed) iphone/USB functionality that I had bought this car radio.