| 摘要 |
PROBLEM TO BE SOLVED: To maintain basic functions for a head lamp, a wiper, etc., even when any trouble occurs in a CPU or the like in a driving unit in a state that a back up line connecting a column switch to a coil of the driving unit is detached and data outputted from an option unit are preferentially treated. SOLUTION: When any trouble occurs in a CPU 6, a power transis-tor 7 or the like built in the driving unit 12 in the vehicle multiplex communication system 1, the option unit 17 detects the trouble, inputs data specifying the driving unit 12 as a transmis-sion destination from a communication line 2, generates a backup driving signal based on the data, and sends the signal to a backup line 18 so as to directly control a coil 8 of the unit 12. |
