| 摘要 |
PROBLEM TO BE SOLVED: To decrease the number of signals inputted into an ECU and the number of digital input ports by monitoring a driving condition in which two signals transmitted from various apparatuses subjected to self-diagnosis are combined. SOLUTION: This apparatus for controlling self-diagnosis of stepping motor combines two driving conditions of respective phase windings in even-numbered driving windings 104 to 107 of at least two phases a stepping motor 103 owns, and detects them. The failure in any of the means of systems ranging from respective phase windings to the driving means of the stepping motor 103 is compared with a combination signal in the normal case by a CPU 102 for determination of failure. If the CPU 102 finds presence of any failure, the two windings of a phase taken as being normal are driven to retreat a flow control valve in a safe direction. It is thus possible to reduce the number of signals inputted into the ECU, thereby reducing the number of digital input ports. |
