To improve drivability by properly determining the occurrence of an abnormality that abnormality cannot be detected unless a shift stage is actually formed in an abnormality determination device of a vehicle having a stepped automatic transmission in which a plurality of shift stages can be formed.

When the information on the abnormality of the element related to the formation of a high-speed stage H determined by an abnormality determination means 136 is stored by a storage means 138 when the vehicle is started to run, the high-speed stage H is established by a shift stage establishment means 144 for re-determination to re-determine the abnormality of the element related to the formation of the high-speed stage H. Therefore, the abnormality that cannot be detected unless the high-speed stage H is actually formed is pre-determined before the vehicle runs. For example, when an abnormality occurs, a fail-safe operation can be performed to prohibit the shift to the high-speed stage H. When the vehicle is recovered to a normal state, the shift to the high-speed stage H can be performed to improve drivability.

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