Check the run pause switch on the top of the water valve lid and make sure it is in the Run position. (picture)
Make sure the gauge pressure is in the 17 to 25 psi range.When in this range the valve should switch about every 45 to 60 seconds.
Try cleaning the Module and make sure the gears will rotate when you spin the one closest to the center pin.
Normal life span of a module is an average 5 to 8 years. This is an average depending on conditions you may need to replace it sooner or later than that.
If the gauge pressure is way higher than normal on the water valve especially on one port, then a nozzle or nozzles may be blocked with debris. To test this, remove the module (Six port modules only) On a single water valve if the water valve stops on one port or circuit shut off the pump and open the water valve. Remove the module and rinse it in the pool or with a hose and reinstall it one position clockwise and close the water valve and restart the pump.   If it goes back to the same set of nozzles and stops again then that is a sign that the circuit has a blocked or improperly sized nozzle(s) and that the water valve module is not the problem. Remove the nozzle(s) on that circuit (keeping in mind that each nozzle must go back in the exact same body from where it was removed.  Check the nozzles for debris or jet size.