A signal processing system that includes a transmitter component, a receiver component, a comparison component and an execution component is provided. The transmitter component transmits a predetermined detection signal, using one or other of a plurality of signal lines of a transmission path. The receiver component receives an interference signal, occurring in a different signal line from the signal line the transmitter component used for transmitting the detection signal, the interference signal occurring from interference due to the detection signal transmitted from the transmitter component. The comparison component compares a voltage value of the interference signal received by the receiver component with a predetermined reference voltage value. The execution component, based on a comparison result of comparison by the comparison component, executes predetermined processing according to the comparison result.