| 摘要 |
PURPOSE:To achieve failure diagnosis without requiring a device for inputting a signal to an acceleration sensor by comparing an output of the acceleration sensor which detects collision and that of other sensors which detect movement other than collision. CONSTITUTION:A signal where acceleration is converted to an electrical signal is generated from an acceleration sensor 21. An ignition criterion circuit 22 receives this signal, judges whether a vehicle collision occurred or not, and develops an air back as needed. When the acceleration sensor 21 is malfunctioning, failure of the sensor 21 is determined depending on whether a small output is generated from the sensor 21 at the time of deceleration by monitoring an output of another sensor 24, etc., which can detect deceleration of the vehicle. When a sensor output monitoring circuit 25 determines failure of the sensor 21, an alarm device 26 generates an alarm and reports it to a driver, thus enabling a failure to be detected without feeding signal to the acceleration sensor. |
