An integrated circuit has an analog output circuit for outputting an analog signal and a leadless terminal for connecting an output line of the analog output circuit to a circuit board by soldering, and measures and transfers an analog output voltage of the leadless terminal in a state in which it is mounted on the circuit board. A measuring unit has a switching unit for connecting the analog output circuit to the measuring unit upon failure diagnosis, and an AD converter for measuring the analog output voltage of the leadless terminal in a failure diagnosis state obtained by the switching unit; and causes the analog output voltage of the leadless terminal to be determined whether it is a normal voltage or an abnormal voltage by transferring the voltage measured by the AD converter to a determination unit through serial transfer.