A method for controlling a steer-by-wire steering system for a motor vehicle comprising an electronically controllable steering actuator which acts on steered wheels and which detects an actual steering angle (α) of the steered wheels, a feedback actuator which detects a desired steering angle (β) set via a steering wheel, and an activation unit which activates the steering actuator in accordance with the desired steering angle (β) and the actual steering angle (α) with a checked torque request signal (PT req), wherein the method comprises the following steps: - determining a torque request signal (T req) by a position controller of the activation unit based at least on the desired steering angle (β) and the actual steering angle (α), - checking by a checking device of the activation unit whether there is an error state of the position controller, - selecting the torque request signal (T req) as a checked torque request signal (PT req) by a selection device of the checking device if the error state has not been determined, - selecting a reference torque signal (T ref) as a checked torque request signal (PT req) by a selection device of the checking device if the error state has been determined, - transmitting the checked torque request signal (PT req) to the steering actuator, characterized in that, by evaluating a cumulative deviation variable, which is calculated by a calculation unit of the checking device as a time integral over a control deviation (e) between the desired steering angle (β) and actual steering angle (α), the checking device determines whether the error state is present and determines the reference torque signal (T ref) by means of a reference controller based at least on the control deviation (e). wherein the method comprises the following steps: - determining a torque request signal (T req) by a position controller of the activation unit based at least on the desired steering angle (β) and the actual steering angle (α), - checking by a checking device of the activation unit whether there is an error state of the position controller, - selecting the torque request signal (T req) as a checked torque request signal (PT req) by a selection device of the checking device if the error state has not been determined, - selecting a reference torque signal (T ref) as a checked torque request signal (PT req) by a selection device of the checking device if the error state has been determined, - transmitting the checked torque request signal (PT req) to the steering actuator, - determining a torque request signal (T req) by a position controller of the activation unit based at least on the desired steering angle (β) and the actual steering angle (α), - checking by a checking device of the activation unit whether there is an error state of the position controller, - selecting the torque request signal (T req) as a checked torque request signal (PT req) by a selection device of the checking device if the error state has not been determined, - selecting a reference torque signal (T ref) as a checked torque request signal (PT req) by a selection device of the checking device if the error state has been determined, - transmitting the checked torque request signal (PT req) to the steering actuator, characterized in that, by evaluating a cumulative deviation variable, which is calculated by a calculation unit of the checking device as a time integral over a control deviation (e) between the desired steering angle (β) and actual steering angle (α), the checking device determines whether the error state is present and determines the reference torque signal (T ref) by means of a reference controller based at least on the control deviation (e).