A system and method for controlling the imaging device in a single pass multi color electrophotographic printing machine, includes a photoconductive member defining a timing aperture, the member moving along a path in a printing machine and a plurality of imaging devices, each one of the plurality of imaging devices writing a latent image on the photoconductive member. The system further includes a sensor, located adjacent the photoconductive member, to sense the aperture in the photoconductive member as it passes the sensor and generate a signal indicative thereof and a control device, which generates a timing signal for each of the plurality of imaging devices as a function of the signal generated by the sensor and a plurality of predetermined parameters.