| 摘要 |
PROBLEM TO BE SOLVED: To diagnose a negative pressure sensor (58) provided to a brake booster (53) in a hybrid vehicle having an engine (1) and a motor generator (2).SOLUTION: A diagnosis includes a "decrease diagnosis" (S5) performed under a situation in which a negative pressure decreases, and an "increase diagnosis" (S7) performed under a situation in which the negative pressure increases. As for the "decrease diagnosis," in an "EV mode" in which a suction negative pressure of an engine (1) does not occur, a negative pressure estimation value NPo is calculated from a negative pressure detection value NPs immediately before a brake operation is started and a brake stroke L (S16), and it is determined that a negative pressure sensor (58) is abnormal (S20) if a detection value NP of the negative pressure sensor (58) is larger than "NPo+α" (S17). |
