Vehicle failure-factor specifying apparatus

A vehicle failure-factor specifying apparatus configured, in event of a certain failure in a vehicle in execution of a certain control operation, to specify a failure-causing driving state that caused the certain failure, the vehicle failure-factor specifying apparatus comprising:

• a peculiarity-presence determining portion configured, in the event of the certain failure in the vehicle, to determine, based on pre-failure data representing a pre-failure driving state that is a certain driving state in a stage prior to occurrence of the certain failure, whether a peculiarity has been present or absent in the pre-failure driving state of the vehicle;
• and
• a failure-causing-driving-state specifying portion configured, when the peculiarity-presence determining portion determines that the peculiarity has been present in the pre-failure driving state of the vehicle in the event of the certain failure in the vehicle, to determine whether the peculiarity present in the pre-failure driving state of the vehicle is substantially identical with a peculiarity that has been determined present in the pre-failure driving state of at least one other vehicle other than the vehicle in the event of the certain failure in the at least one other vehicle,
• wherein the failure-causing-driving-state specifying portion specifies the pre-failure driving state as the failure-causing driving state, when determining that the peculiarity present in the pre-failure driving state of the vehicle is substantially identical with the peculiarity present in the pre-failure driving state of each of the at least one other vehicle, and
• wherein the peculiarity-presence determining portion determines whether the peculiarity has been present or absent in the pre-failure driving state of the vehicle, depending on whether a frequency distribution of the pre-failure driving state of the vehicle is deviated from a frequency distribution of a non-failure driving state that is the certain driving state of each of a plurality of vehicles including the at least one other vehicle in a non-failure case in which the certain control operation is executed satisfactorily in the each of the plurality of vehicles.