| 摘要 |
PROBLEM TO BE SOLVED: To provide a failure diagnostic device that can accurately diagnose failure of a brake switch without providing an additional sensor for diagnosing brake failure.SOLUTION: In a time zone (T1 or T2) before or after a vehicle speed detected by a vehicle speed sensor has reached a predetermined speed threshold value (V2) or lower that determines a vehicle stop state, if an accelerator opening detected by an accelerator position sensor is in an accelerator off state, a determination that vehicle acceleration detected by a G sensor satisfies a predetermined condition is made and a brake switch state detection section detects that a brake switch is in an off state, a fault diagnosis determination section determines that the brake switch is abnormal. The predetermined condition is that the vehicle acceleration detected by the G sensor exceeds a predetermined acceleration threshold value (G1) or that a time change rate of the vehicle acceleration exceeds a predetermined time change rate threshold value.SELECTED DRAWING: Figure 4 |
