DIAGNOSIS SYSTEM, VEHICLE, METHOD, AND COMPUTER-READABLE STORAGE MEDIUM

A diagnosis system performs, while a vehicle is being driven, a diagnosis of a rotation portion of a rotating electrical machine included in the vehicle. The diagnosis system includes a measurement unit that, when performing the diagnosis of the rotation portion, stops charging of a storage battery included in the vehicle from the rotating electrical machine, and measures an inductive voltage of the rotating electrical machine generated by a rotation of the rotation portion, and a judgment unit that judges that there is an anomaly in the rotation portion when a magnitude of the inductive voltage is equal to or larger than a predetermined value.