FAULT DIAGNOSTIC SYSTEM FOR CURRENT SENSOR

PROBLEM TO BE SOLVED: To provide a fault diagnostic system for a current sensor which can easily and surely diagnose output fixing abnormality in a current sensor detecting the charging/discharging current of a battery and easily avoid false diagnosis at output clamping, when the output range of the current sensor is provided. SOLUTION: When the difference between the present value and the previous value of the current sensor output represents the predetermined value A or smaller, it is decided that there is a possibility of output fixing, and the present value is stored. Whether the difference between the stored value and the detected output value of the current sensor is the predetermined value A or smaller is decided. When it is the predetermined value or smaller, a timer is made to count. When the timing by the timer has continued for a predetermined time period, it is decided that there is an output fixing abnormality in the current sensor. COPYRIGHT: (C)2007,JPO&INPIT