A two-door passenger motor vehicle is provided with a mechanism for feeding a locking clasp and/or belt strap of a seat belt system, with the mechanism including an overload safety device for stopping a motor of the feeding mechanism so as to protect it and a power source, such as a vehicle battery, from damages when an obstacle is projected into the course of movement of the feeder arm, or the feeder arm is in an end position and is no longer reversed or switched off. The overload safety device also responds in the case of a delay-dependent blocking of the belt strap, but initiates a new feeding movement. When the front end position is reached, an automatic return of the feeder arm by a predetermined amount takes place so as to release a blocking effect of a belt roller of the seat belt system and the feeder arm is then subsequently returned to a retracted position.