Fault diagnosis method fault diagnosis system, and fault diagnosis equipment

摘要

PPROBLEM TO BE SOLVED: To provide a failure diagnostic system etc. capable of specifying a failure occurrence condition even in the event of a failure by a cause that is not anticipated beforehand, and maintaining the operational performance of a vehicle while suppressing the storage of a log to the requisite minimum in the event of the failure. PSOLUTION: The failure diagnostic device compares normal data to abnormal data to calculate a difference set (S105), determines whether or not a failure occurrence condition can be calculated (S106), and when it is determined that the failure occurrence condition cannot be calculated (NO in S106), gives an alteration instruction to a data log acquisition device to acquire a state value of a level of abstraction lower than the previous one (S107). When it is determined that the failure occurrence condition can be calculated (YES in S106), the failure diagnostic device performs formulation to a form of a maximum satisfiability problem (MAXSAT) (S108), calculates the failure occurrence condition (S109), and gives an alteration instruction to the data log acquisition device to acquire an input/output signal of a rank lower than the previous one (S110). PCOPYRIGHT: (C)2011,JPO&INPIT