Tv Picture Goes Out

Normally this is an indication that you have a bad lamp, but really what this indication is, the microprocessor has not received the signal from the optical engine that "the lamp is lit and all is well". There are many things that need to happen before the lamp will start up. The power supply must develop all the needed voltages required by all the rest of the circuits, the cooling fans must be running at the correct speeds, the lamp door switch must be closed (interlock switch), The Color Wheel must be able to spin at the 1800 RPM and lock in sync with the video signal, the ballast circuit must be able to develop the 5000 volts to start-up the mercury vapor lamp, and the lamp needs to be in good working condition to light up. There should be no weird noises pointing to the fact that a fan or the color wheels motor bearings are starting to go bad. The normal failures are the lamp and the color wheel. Unfortunately there is NO way to test a lamp. I have seen nearly 100 lamps come into my shop that has failed in less than a month, and many that didn't last one full day. These lamp you buy off the web are many times factory seconds. I have had some customers send back a lamp two, three, and four times before they got one that lasted through the warranty. Our shop only buys from the manufacturer. When you turn on this DLP HDTV the fans will start up first and then the color wheel will spin-up. If the color wheel doesn't get up to the 1800 RPM and maintain that speed then the lamp will not get to enable pulse. unfortunately after three attempts the set will shut down and the indicators will blink telling the customer to change the lamp, and of course after the customer does it, the problem remains the same. The microprocessor is located in the signal cluster and all it knows is that the lamp didn't light up correctly, so it gives the change lamp LED indicator blink

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TV Dan