| 摘要 |
PURPOSE:To repair efficiently a fault by conducting plural loads through an input/output interface when the fault is detected, also applying a load current to a current detecting circuit, and detecting as an abnormality in case when a prescribed current is not detected by the current detecting circuit. CONSTITUTION:At the time of a fault detecting operation, plural loads are conducted successively through an input/output interface, also a current flowing to the load is applied to a current detecting circuit, and when a prescribed current is not detected by the current detecting circuit, it is detected as an abnormality. In case of an output is not generated in an output terminal Q0 of the input/ output interface 3, and a switch 5 is at a contact (a) side, current paths W1-Wn containing loads L1-Ln and switching elements S1-Sn are formed. Subsequently, when a control signal is generated in the output terminal Q0 of the input/output interface 3, current circuits W1-Wn containing a resistance Rp are formed successively. In this case, unless a fault exists in the inside of the circuit, the current flows successively to the circuits W1-Wn, and a pulse signal PX is inputted. Therefore, a CPU1 does not apply a signal to a display interface 9, and it is detected that no fault is generated in the current path. |
