Present invention relates to an automatic door operator 10 and method of operating said automatic door operator 10. The automatic door operator 10 is arranged to operate the movable door member D1, said automatic door operator 10 comprising a drive unit 24 for moving the movable door member D1 between a closed position and an open position, a controller 32 configured to control said drive unit 24 and a sensor S1 operatively connected to said controller 32. The sensor is configured to monitor the operation of the movable door member D1 and transfer sensor data to said controller 32.