A watercraft propelled by an outboard motor includes an inspection system. The inspection system includes a terminal computer that conducts an inspection of an engine control device and a control unit. The computer includes a program that performs an inspection process that provides the control device with a command signal to start an inspection of the control device and that requests the control device to output a first response signal. The process determines whether the response signal is consistent with a first specified signal. The process provides the control unit with a command signal to start an inspection of the control unit and requests the control unit to output a second response signal. The process determines whether the second response signal is consistent with a second specified signal. The control device controls a throttle actuator and a shift actuator based upon the second response signal and provides the inspection system with an operating signal. The process determines whether the operating signal is consistent with the second specified signal. The computer includes an indicator panel or other display device to show the results of the determinations made by the inspection process.