If the sync module is enabled, and the camera has the blue running man, then you are set to detect motion. The only other normal setting that could affect it is the sensitivity level. If this is very low, by accident, like set at 1, it is very difficult to trigger motion. 5 is the default.
If all above is done, and you have tried rebooting the sync module, I know you have with the camera, then maybe you have a faulty camera, and should log a support ticket.