The invention relates to a method for controlling a light signal system, wherein - in a first time interval of the light signal system, signal times of a signal group of the light signal system are determined for a second time interval which follows the first time interval in time on the basis of measured traffic data, wherein - the determined signal times are kept unchanged after a predetermined time, wherein - the signal group is controlled in the second time interval on the basis of the signal times which are kept unchanged so that the signal group outputs signals corresponding to the signal times which are kept unchanged in the second time interval, - wherein rest times for the signal images of the signals are determined from the signal times which are kept unchanged if the signals are switched in the second time interval, - wherein the predetermined time is determined in such a way that the rest times determined for each future time remain unchanged for signal images of the light signal system which are running at that time and that the next switching time of a signal is present at the latest at the time of the preceding switching time. The invention furthermore relates to a light signal system control system for controlling a light signal system and to a computer program.