| 摘要 |
PROBLEM TO BE SOLVED: To surely detect a fault of a slave ECU (electronic controller) through information communication between a master ECU and the slave ECU. SOLUTION: Power is fed from a master ECU 1 to a slave ECU 2 through a power supply line 3. A transmission circuit 22 in the ECU 2 transmits data to a receiving circuit 12 of the ECU 1 through the line 3. A microcomputer 20 of the ECU 2 is reset by the power-on reset function and watch dog reset function of a power supply circuit 21 having a WDT(watch dog timer). In an operation after the reset, 1st specific information is transmitted from the ECU 2 to the ECU 1 to represent that the reset is performed. The ECU 1 counts the number of watch dog resets of the ECU 2 except the reception of the 1st specific information just after starting power supply, decides as a fault when it exceeds plural times that are previously defined and switches on a lamp 9, etc. |
