Abstract: A trouble diagnosis device of a vehicle body acceleration sensor by determining that the output fixing trouble of the vehicle body acceleration sensor or the like is not generated at a point of time that the fluctuation width of the output value of a vehicle body acceleration sensor becomes a predetermined value or above during the traveling of the vehicle with the vehicle speed equal to or more than the predetermined speed, and by stopping the trouble diagnosis of the output fixing trouble of the vehicle body acceleration sensor or the like until the vehicle speed is lowered to a value less than the predetermined speed thereafter, it is possible to avoid the trouble diagnosis of the output fixing trouble of the vehicle body acceleration sensor or the like when that the trouble diagnosis of the output fixing trouble of the vehicle body acceleration sensor or the like is unnecessary.

Abstract: The present invention reduces a control processing load of a vehicle-use antilock brake system attributed to a trouble diagnosis of a sensor which is mounted on a vehicle and has an output thereof changed corresponding to a traveling state of the vehicle during traveling of the vehicle, particularly a vehicle body acceleration sensor which detects the vehicle body acceleration of the vehicle. From a point of time that a vehicle speed becomes a preset speed ? (4 m/s) or more (timing indicated by symbol T1), the storing and the updating of a maximum value Gmax and a minimum value Gmin of an output value of the vehicle body acceleration sensor 1 are started and it is determined whether the difference between the maximum value Gmax and the minimum value Gmin, that is, a fluctuation width of the output value of the vehicle body acceleration sensor 1 becomes a preset fluctuation width ? or more or not.

Abstract: By a method for detecting an output-stuck fault of a car body acceleration sensor, an absolute value of a relative difference between the logical car body acceleration operated on the basis of a wheel speed and the physical car body acceleration output from a car body acceleration sensor is obtained, and the obtained absolute value of the relative difference is compared with a first rated value. When the absolute value of the relative difference exceeds the first rated value, a fail counter is made to start to count up at that point of time. When a counted value of the fail counter exceeds one second during the absolute value of the relative difference is exceeding the first rated value, the difference of the maximum value and the minimum value of the physical car body acceleration during the period is compared with a second rated value.

Abstract: By a method for detecting an output-stuck fault of a car body acceleration sensor, an absolute value of a relative difference between the logical car body acceleration operated on the basis of a wheel speed and the physical car body acceleration output from a car body acceleration sensor is obtained, and the obtained absolute value of the relative difference is compared with a first rated value. When the absolute value of the relative difference exceeds the first rated value, a fail counter is made to start to count up at that point of time. When a counted value of the fail counter exceeds one second during the absolute value of the relative difference is exceeding the first rated value, the difference of the maximum value and the minimum value of the physical car body acceleration during the period is compared with a second rated value.