This paper presents the fault tolerant control algorithm for Brake-By-Wire system. The objective of the controller is to follow driver's desired deceleration with simultaneous lateral stability in spite of fault. The proposed controller is based on sliding mode control theory which let the controller to have robustness against disturbances. Furthermore, a fault diagnosis to determine the size of the fault is performed by the recursive least square method. Then, the controller after determining the size is derived to either alleviate or maintain the usage of the faulty brake.