VORRICHTUNG UND VERFAHREN ZUR AUSFALLSICHERUNGSSTEUERUNG FUER ELEKTRONISCH GESTEUERTE, AUTOMATISCHE GETRIEBE

摘要

In a fail-safe control device for an electronically controlled automatic transmission to be mounted on a vehicle, a sensor for the number of revolution input to a T/M is newly provided for the electronically controlled automatic transmission, and an actual gear ratio of the T/M is calculated in accordance with the number of revolution input to the T/M and the number of revolution output from the T/M or the car speed. If the calculated actual gear ratio is coincided with the formal gear ratio, it is determined that the state is normal, while if they are not coincided with each other, it is determined that the T/M is in a failure state. As a result of this, failure detection of the T/M is performed. Therefore, in a case when the T/M is in a failure state, a driver can take a measure, for exmple, by performing an emergency control. Furthermore, the occurrence of the failure can be displayed by a detected failure displaying device so that the driver can take a measure such as a repair.