A microprocessor-controlled web guidance system which automatically implements and maintains a proper lateral web alignment of a continuous web in a web printing press. A steering mechanism is provided which is controlled by a microprocessor system which utilizes infrared radiation for edge detection wherein multiple sensors are driven by means of stepper motors driving on a flexible linear cogged belt system. The system includes novel functions, and diagnostic and maintenance modes which may be programmed by the operator. A plurality of control panels are provided to enable the operator to select and program desired functions and to access desired modes. Self calibration and testing of the steering mechanism and the edge sensors is also provided.
