| 摘要 |
A microcomputer 17 detects and determines whether a problem exists in a power supply breaker of an ECU 11 functioning as a motor controller. Specifically, the microcomputer 17 determines whether there is a malfunction caused by a short circuit in a first FET 26 based on the output voltage V1 and output voltage V2 that are detected in a first FET 26 and a second FET 27, respectively, when the switching states of the first and second FETs 26, 27 are both off. Afterwards, the microcomputer 17 determines whether there is a malfunction caused by a break in the first FET 26 based on the output voltages V1, V2 of the first and second FETs 26, 27 that are detected when only the first FET 26 is switched on. If the microcomputer 17 determines that the first FET 26 is free from any malfunction, the microcomputer 17 determines whether there is a malfunction caused by a short circuit or a break in the second FET 27 by comparing the output voltage V1 of the first FET 26 and a charge voltage Vc of a smoothing capacitor 22 that are detected afterwards. |
