A method (1000) for testing of a door operator (100), the door operator (100) being configured to via a mechanism (104) move at least one door leaf (200) between a first position and a second position. The door operator (100) includes a first drive unit (102) configured to optionally move the door leaf (200) into said first position and a control unit (103) connected to a sensor (105). The method includes the steps of initiating a simulated powerless mode, measuring operation of the door leaf by the sensor, and comparing measured values of movement with reference values.