To a self-diagnosis indication system for performing a startup disablement indication when an abnormal condition is self-detected at the time of start up without using on/off signals from a starter switch. There is provided a self-diagnosis indication system for outputting an operation control signal from an ECU by allowing signals from respective types of sensors for detecting an operating condition and a crank pulse signal for detecting a rotation of a crankshaft to enter the ECU and outputting a startup disablement indication signal in a state that an abnormal condition is self-detected at the time of startup, the self-diagnosis indication system being characterized in that a startup disablement indication signal is outputted when a crank pulse signal is inputted in the state that an abnormal condition is self-detected at the time of startup.