Like other manufacturers, Hitachi makes a variety of video projectors, and each model has slightly different maintenance requirements. There are a number of common problems that may surface from time to time, including blank or blurry images, maintenance warnings and apparent power failures. Fortunately, the majority of these issues don't indicate a serious projector malfunction, and can be resolved by running through a brief checklist of common solutions.
Turn off the projector and let it cool for 20 minutes if the projector's power light is solid or blinking red, which generally indicates an issue with the projector's temperature or cooling system. Check the projector's fan and air intake for obstructions, and make sure the projector's lamp cover is properly secured.
Check your cables. Make sure both ends of any power or video cables are plugged in and connected properly---unplug them, then firmly reseat each cable.
Check that the projector is set to the correct video input source and that the lens cap is removed. Also check whether the projector's "Blank" feature is active, which causes the projector to display a black screen.
Check the projector's video settings. Its brightness may be extremely low, or its contrast, colour or sharpness settings may be distorting the image quality. If the image is blurry, adjust the projector's focus and check if the lens is dirty.
Make sure your video source is producing a video signal the projector can process. The projector will alert you of this by displaying either "Sync is out of range," or "Invaild scan freq."
Check how many hours the projector lamp has logged. Press the "Menu" button, select "Go to advanced menu," then go to "Option," then "Lamp Time." Check if the lamp has been in use longer than its recommended lifetime; the projector's manual should say how long lamps are usable. Replace any lamps in use longer than their recommended lifetime.
Never attempt to use a projector lamp longer than its recommended lifetime. They contain pressurised gases that sometimes cause overused lamps to explode, possibly scattering shattered glass in a large area.