| 摘要 |
PURPOSE:To avoid erroneous decision in a reverse drive condition, in the case of deciding abnormality of an automatic transmission using an engine speed as a transmission input rotational speed, by performing this abnormality decision when placed in a forward drive condition. CONSTITUTION:In a controller 6, a speed change shift command to solenoids 4, 5 is determined from a throttle opening TH and car speed V, to put an automatic transmission 2 into a corresponding speed change shift. When ratio of an output rotational speed No relating to an engine speed Ne displays a mismatching value relating to the speed change shift command, the controller 6 outputs an abnormality signal to a display device 13. Thus by permitting the abnormality decision when discriminated in a forward drive condition from the throttle opening TH and the car speed V, erroneous decision at reverse drive time due to a one-way clutch of the transmission, generated in a conventional device permitting this abnormality decision when a torque converter is placed in a lockup condition, can be avoided. |
