The present invention comprises: a synchronization start determination unit 110 for determining a synchronization start of a synchronization device 70; a half-clutch determination unit 130 for determining whether a clutch device 20 is in a half-clutch state where the clutch device has not been switched from a connection state to a disconnection state; and a damage determination unit 140 which, when the synchronization start determination unit 110 has determined the synchronization start and if the half-cutch determination unit 130 has determined a half-clutch state, determines that damage is applied to the synchronization device 70 caused by the differential rotation between the power transmitted from a driving force source 10 side via the clutch device 20 and the power transmitted from a driving wheels 16L, 16R side.