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Hello guys,
I have a weird problem on this 820-2330 logic board I’am working on, the backlight circuit only produced 14,4volts on lcd output. I replaced the baclight chip three times and still can’t get the boost circuit to work. All resistors are good around the chip and there is no broken traces anywhere. Can anyone shed some light on this problem?
Thanks you!
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893
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Roger WE really do not have enough information. It’ll help if you can tell us where you are measuring your voltage and check the voltage on Q9701 and L9701. Also, let us know if you measured/checked any other components or if you are assuming that they are in good working condition.
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Oldturkey did you receive my email?
sure did not
Roger - Have you reviewed Louis Rossmann's vids? He has a couple of good ones on backlight issues.
Yes Dan I have viewed those videos! I can t understand if I have 12.6v on pins 1,2,5,6 on Q9701, why would I only get 14.4 on lcd output. Something is not right of course! Why isn't the u7901 chip boosting that rail?
Did you replace the inductor L9701?
Was this system wet?
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Also the LVDS connector is in good shape too!
crwdns2934271:0crwdnd2934271:0 Roger crwdne2934271:0