| 摘要 |
PROBLEM TO BE SOLVED: To provide an inexpensive and simple vehicle communication network system by applying serial data line for diagnosing fault. SOLUTION: A diagnostic tester 7 diagnoses the presence/absence of the fault of a unit 3an, units 3b1 to 3bn are connected with a bus 4 to transmit and receive data between them and the bus 4 expresses data inputted from the units 3b1 to 3bn with an indicator or a numerical value. A relay 27 connects the tester 7 to the unit 3an through a serial data line 1 at the time of diagnosing the unit 3an and connects a meter 5 to the unit 3an through the line 1 at the time of communicating between the meter 5 and the unit 3an. |
