Check the LED lamps on the projector for information. You may need to have the lamp replaced or filter cleaned.
After overheating or an electrical outage or surge, some projectors may not power on. The projector may show an abnormal flashing led sequence. This is due to built in protection for the projector. Simply unplug the power cord from the wall which is normally directly below the projector. Wait a few seconds, plug it back in and the projector should work normally.