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dell plazma w4201c hd

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pioneergroup:
hello , any body find what the problem for dell w4201c hd no display all voltage are ok.

Va - 70 Vdc - 70.3 Vdc
Vs - 207 Vdc - 209 Vdc
Vsc - 190 Vdc - 191 Vdc
Ve - 84 Vdc - 84.2 Vdc
Vset - 190 Vdc - 191.1 Vdc
12V - 12.03 Vdc
5V - 5.22 Vdc
also i check for bad capacitors but nothing. green LED2010 is on and second green LED2011 main logic board (LJ92-01270E) blinking.

Ere:
Solution: The power board of the W3201C HD has 2 electrolytic caps that are under-rated and tend to cause problems with the basic power supply needed by the main board. When they dry too much the main board just fails to operate normally and the TV, upon initial power-on hangs in an undefined state where pretty much the only thing you can do is power it back off. Sometimes it powers off by itself after you wait enough.




The power board is the large green board with many heat sinks and transformers in the upper half of the TV. You can unplug all connectors (no need to remember which is goes where - can't confuse them) likely except the one in the middle bottom part.
To unplug that one you'll need to carefully unscrew all the bolts holding the board in place and pull the board upwards a bit. I strongly recommend using a magnetic screwdriver so that you don't end up chasing screws around the TV body. This is dangerous and may hurt.

What you're looking for is a pair (or more) of capacitors in the highlighted area that have swollen / bulged tops.

The swollen / bulged capacitors are a common visual, but not ultimate indication of bad caps. If yours aren't bulged they may still be bad and even if they're not we still recommend replacing them because it is only a matter of time before they turn bad unless they have already been replaced with others with higher voltage rating. don't think that y-sus board or z-sus are bad, just replace these caps and i'm very sure your tv will be brought back to life again ...
Measurements on the power supply card showed that all voltages were within tolerance except the 5v reading, which was 4.2v - 5v. These caps are part of the circuit for the 5v output to the logic board in the TV. The insufficient voltage was apparently enough to prevent the TV from powering on the screen and sound.

pioneergroup:
thanks friend but i have all ready change these capacitors those capacitors are for main board power supply.finaly i found STK 795.i change its ok now.

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