| 摘要 |
PURPOSE:To allow detection and diagnosis of an incidental failure by providing, in the process of determining a control signal by a control unit, means for discriminating whether object signals are normal or abnormal and means for storing the state at discrimination of any abnormality. CONSTITUTION:When an air conditioning switch 93 is turned on and a microprocessor 90 executes an air conditioning program, a control signal S3n is determined according to an operation signal S1l and a sensor signal S2m so as to drive an actuator 4. At the same time, the signal S2m from the sensor 6 is entered into a discriminating circuit 91. Similarly, the signal S3n from the actuator 4 and signal S1l from the operation switch 5 are entered into the discriminating circuit 91. It is discriminated whether they are normal or abnormal. As the result, R1l, R2m, R3n are entered into the microprocessor 90, and if there is any abnormality, a RAM 92 stores it. When a diagnosis starting switch is turned on, the abnormality stored is indicated at 12. Thus, an incidental failure can be detected. |
