Proscan LCD flat panal model #plded3992a-c. Hello. I turn monitor on, blue screen is dim and blinks. Will not hold picture. Power? Or bad card?

SOURCE: 32 in Magnavox tv model 32MF231D/37

An earlier post of the smaller model of this with the same problem said to remove the metal cover over the power supply.

I have the 26MF231D and it worked great afterward (even though you can't mount it)

Here is how you remove the cover.
http://www.flickr.com/photos/88002248@N00/sets/72157611665895426/

SOURCE: seems as if LCD screen is not recieving any power, I have no picture or sound right now but can faintly hear speakers power up when I turn the unit on.

Mainboard damaged.

SOURCE: rca L32hd31 lcd no picture blank screen.

Your mainboard is damaged, replace it and that will solve your issue.

SOURCE: DVD Hook up to Proscan TV

if using RCA connector cables, connect the left and right audio cables to D and D1, then connect the Video cable to the video connector right above the S Video port.

SOURCE: 26" Samsung flatscreen LCD doesn't power up

Just to be a little more detailed, since I just fixed this problem. It is the capacitors are the problem. However, I think that if you have some minimal skills with soldering, you can fix this yourself. You just need to take out the system board, then the power supply parts are on the top right. The bad capacitor(s) will be bulging at the top and possibly have some brown stuff coming out. The ones that go bad are 1000microfarad, 10V, however you can replace them with higher voltage. I got 35V caps from radio shack for 1.59 each. You just need to solder out the bad ones and then put the new ones in and solder. Remember that the negative end goes on the side with the bold black part of the circle on the system board. Then just cut off the extra ends of the capacitors. If you are capable of doing this yourself, you will spend at most 6 dollars instead of however much a technician costs.