Failure diagnosis apparatus and failure diagnosis method of vehicular electronic control system

A failure diagnosis apparatus for diagnosing a failure in a vehicular electronic control system, comprising:

• a plurality of electronic control related members including electronic control apparatus mounted on a vehicle and controllers for electronically controlling the electronic control apparatus;
• a multiplex communication system including a multiplex communication line connected to the plurality of electronic control related members as communication elements;
• a recording portion recorded with states of the electronic control apparatus and proper value data of the plurality of electronic control related members with regard to the states of the electronic control apparatus in correspondence with each other;
• a detecting portion for detecting respective states of the plurality of electronic control related members based on communication signal information received from the multiplex communication line;
• and
• a display portion for displaying the proper value data recorded in the recording portion and detected data detected by the detecting portion, or either of the proper value data recorded in the recording portion and the detected data detected by the detecting portion.

A failure diagnosis method for diagnosing a failure in a vehicular electronic control system including, a plurality of electronic control related members having electronic control apparatus mounted on a vehicle and controllers for electronically controlling the electronic control apparatus, and a multiple communication system having a multiple communication line connected to the plurality of electronic control related members as communication elements, said failure diagnosis method comprising:

• receiving communication signal information from the multiplex communication line;
• specifying a region which may have failed in the multiplex communication system from the communication signal information received in the receiving step based on presence or absence of communication by the plurality of electronic control related members;
• and
• specifying the electronic control related member which may have failed in the plurality of electronic control related members based on a data content of a communication signal provided from the communication signal information.

A failure diagnosis method for diagnosing a failure in a vehicular electronic control system including a plurality of electronic control related members having electronic control apparatus mounted in a vehicle and controllers for electronically controlling the electronic control apparatus, and a multiple communication system having a multiple communication line connected to the plurality of electronic control related members as communication elements, said failure diagnosis method comprising:

• recording states of the electronic control apparatus and proper value data of the plurality of electronic control related members with regard to the states the electronic control apparatus in correspondence with each other;
• detecting respective states of the plurality of electronic control related members based on communication signal information received from the multiple communication line;
• and
• displaying the recorded proper value data and detected data detected by the detecting step, or either of the proper value data recorded by the recording step and the detected data detected by the detecting step.