Abstract: Secure failure diagnosis of a brake switch is enabled with a simple configuration. Inconsistency detection is performed for output signals from two brake switches 6a and 6b provided such that an operation condition of a brake pedal 1 may be detected (S102), and when inconsistency is detected, after a certain time has passed from the relevant detection point, inconsistency detection is newly performed for output signals from the two brake switches 6a and 6b (S108), and when inconsistency is detected again, a determination counter performs count of a predetermined incremental value, those operation being periodically repeated (S110), and when a count value reaches a predetermined value ? after the determination counter performs the count, the two brake switches 6a and 6b are determined to be failed (S114 and S118).

Abstract: Secure failure of a brake switch is enabled with a simple configuration. When brake switches 6a and 6b are determined to be not ON together and not OFF together (S110 and S112), first and second determination counters perform count respectively (S114 and S120), and on the other hand, when the two brake switches 6a and 6b are determined to be ON together, a count value of the first determination counter is set to zero (S132), and when the brake switches are determined to be OFF together, a count value of the second determination counter is set to zero (S136), those operation being periodically repeated, and when one of the count values of the first and second determination counters exceeds one of respective predetermined values ? and ? (S118 and S214), one of the two brake switches 6a and 6b is determined to be failed, which enables detection of a failure state that one of the brake switches is normally ON or normally OFF.

Abstract: Secure failure of a brake switch is enabled with a simple configuration. When brake switches 6a and 6b are determined to be not ON together and not OFF together (S110 and S112), first and second determination counters perform count respectively (S114 and S120), and on the other hand, when the two brake switches 6a and 6b are determined to be ON together, a count value of the first determination counter is set to zero (S132), and when the brake switches are determined to be OFF together, a count value of the second determination counter is set to zero (S136), those operation being periodically repeated, and when one of the count values of the first and second determination counters exceeds one of respective predetermined values ? and ? (S118 and S214), one of the two brake switches 6a and 6b is determined to be failed, which enables detection of a failure state that one of the brake switches is normally ON or normally OFF.

Abstract: Secure failure diagnosis of a brake switch is enabled with a simple configuration. Inconsistency detection is performed for output signals from two brake switches 6a and 6b provided such that an operation condition of a brake pedal 1 may be detected (S102), and when inconsistency is detected, after a certain time has passed from the relevant detection point, inconsistency detection is newly performed for output signals from the two brake switches 6a and 6b (S108), and when inconsistency is detected again, a determination counter performs count of a predetermined incremental value, those operation being periodically repeated (S110), and when a count value reaches a predetermined value ? after the determination counter performs the count, the two brake switches 6a and 6b are determined to be failed (S114 and S118).