Audio but no pictureb>This is a common issue in many LCD or Plasma sets andit does not have a common solution.In most cases you need to first check for missing voltages on the power supply board and for damaged caps there. If good voltages exist then look elsewhere.LCD (not projection) sets often use a back light to provide the light source for the screen unit (display panel) so confirming the voltage for those is first-if back lights are used but not on it is either no voltage, not being turned on by the set, or bad light unit/s.In these sets there are also boards that "Drive" the panel itself. Usually the set will use two boards (some combineboth into one large board---names vary but are Inverters, Y-boards (Y means video) T-con boards etc. Usually in this case only one half of the screen will be black but it is possible for it to cause a total loss of brightness also.Plasma sets are similar to some degree but with no back light in most cases.Trouble shooting can be tedious and expensive-Taking one of these sets apart requires some skill as one wrong move and the Display panel can be instantly damaged which is fatal from arepair cost point of view.Other possible solutions include but are not limited to physical problems---loose plugs or connections (look for any plugs held down with tape where they plug into aboard). A lot of people with problems play the guessing game-buy and try a board after research which can get expensive and may not fix the set---gamble or not?I have seen sets where every single board was replaced and set still did not have a picture-means display panel is the problem.The problem can even be the "main" board in some cases -it controls the communication with the panel and if faulty can cause issues.Aside from checking voltages, connections etc. there are afew other considerations---The problem can be the display panel itself---Part cost for that is more than the set cost when new.The panel connects to the boards that drive it with either a multi-pin conventional plug or a RIBBON CABLE.The worst case is the problem is a ribbon cable etc. bad or damaged INSIDE the panel where it cannot be got at.That means if the case set would cost too much to repair.The connectors where the cable attaches outside of thepanel can also develop dirty or loose connections.Fans in units that use them can be an issue if dirty or not moving.As you can see (or not if no brightness) the problem sounds simple but has many possible different causes.Let me know if you have questions as I am here to try to help.SDTECH
SOURCE: have a soyo mt-sytpt4227ab for
take the back off and get to the power supply most likely you will find some bad capacitors in it they will probaly have the tops of the caps bulgeing.
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