This paper investigates on sensor fault reconstruction of sensors used for steering control of autonomous vehicle for functional safety. Sensor information such as steering angle and longitudinal velocity is generally needed for the design of steering feedback control system. If there exists unexpected fault signals in sensors, fatal accident can occur during autonomous driving because controller cannot compute the accurate control input. In this study, the sliding mode observer has been designed for fault reconstruction of steering angle and velocity sensors. In order to design the observer, the bicycle model that represents dynamic relationship between steering angle and velocities such as lateral velocity and yaw rate of vehicle has been used. The stability analysis has been conducted in accordance with velocity of the vehicle. The fault signals in sensors have been reconstructed using the injection term in sliding mode observer with the sliding mode gains designed for the stability. The performance evaluation has been conducted in Matlab/Simulink environment under the curved path tracking scenario.