The car radio diagnostic processor is an interface chip in BCD Technology intended for car radio applications. It is able to detect potential faults coming from any misconnection in the car radio or in the harness when installing the set. The device is able to reveal any fault in the loudspeaker lines and in the antenna and booster supply lines, providing a proper output signal (I2C bus compatible) in order to disable the ICs under fault and/or to alert controller by means of warning messages.