Disclosed herein is a method and arrangement for safe limiting of torque overlay intervention in a power assisted steering system of a road vehicle having an autonomous steering function arranged to selectively apply a steering wheel overlay torque to a normal steering assistance torque. A wheel self-aligning torque ( fR ) of the road vehicle (1) is modelled for a current vehicle velocity ( v ) and pinion angle ( [delta]v ) . A steering wheel overlay torque request ( [tau]R ) is received. Based on the received steering wheel overlay torque request ( [tau]R ) is provided a steering wheel overlay torque ( [tau]A ) in hands-off applications limited to a safe set interval that is symmetrical around the modeled wheel self-aligning torque ( fR ).