Device and method for controlling lock-up clutch

The invention provides a device and method for controlling a lock-up clutch. A torque converter (21) provided between an engine (1) and an automatic transmission (2) is provided with a lock-up clutch(21). A device (11) for controlling the lock-up clutch (21) performs control such that the lock-up clutch (21) reaches a first slip amount in a low-vehicle-speed region. If the slip amount remains ina state of being equal to or greater than a second slip amount that is greater than the first slip amount, it is determined that there is an abnormality and the lock-up clutch (21) is released. When there is a request to change the automatic transmission (2) to a lower speed during coasting, the abnormality determination is prohibited in order to avoid an erroneous determination accompanying the change in speed. 本发明提供一种锁止离合器的控制装置及控制方法。本发明的液力变矩器(21)设置在发动机(1)与自动变速器(2)之间，具备锁止离合器(21)。锁止离合器(21)的控制装置(11)在低车速区域将锁止离合器(21)控制为第一滑移量。若滑移量大于第一滑移量的第二滑移量以上的状态继续，则判定为异常，释放锁止离合器(21)。在滑行行驶时有使自动变速器(2)向低速侧变速的请求时，为了避免伴随变速的误判，禁止异常判定。