摘要 |
<P>PROBLEM TO BE SOLVED: To accurately determine a failure of an output shaft speed sensor, ensure stability of a vehicle even when an input shaft speed sensor and the output shaft speed sensor concurrently fail, and perform failure diagnosis without using an output value of a vehicle speed sensor. <P>SOLUTION: This method comprises steps including a concrete determination/ diagnosis procedures. That is, the method comprises the steps of: determining, based on a present shift stage, a signal of the output shaft speed sensor, a signal of the input shaft speed sensor, and a signal of engine speed sensor, and according to a previously set condition, whether the failure diagnosis is carried out or not, and shifting is performed or not; performing optimum shifting; and concurrently performing the failure diagnosis of each of the sensors at this process. <P>COPYRIGHT: (C)2004,JPO |