If you have a TV that does something similar to this image, you might be able to fix it yourself with just a screwdriver. This is sometimes just red, sometimes just green, and other times mixed like in the picture. My tv was covered in red pixels up to 80% of the screen. It started out as just some red dots in the most dark areas, but it increased up to the point when I decided to either fix it, or kill it, so I can get Wife Acceptancy for a LED TV. Well, it so happens that I fixed it without knowing what I was doing, but using my brain.
What you need first is to get the following gear before you start unscrewing anything:
- a flat screwdriver with a 2-3mm head, preferably isolated handle, you can isolate it yourself with some plastic or rubber
- a rubber dish washing glove so you don't kill yourself if the screwdriver makes contact with anything electrified
- a clear dinner table
- a stack of books
- a mirror sized so you can slide it under the TV
- a DVD-player running a movie, connected to the tv on the AV1 channel
- an electric screwdriver, there are a lot of screws
- fine point permanent marker
Then you remove the back panel, by removing all the screws except those under the connectors in my case, that panel is separate. In my case you need to remove the "legs" to remove a couple of the screws. Get some books, put them on the dinner table in 4 equal stacks, and put the TV with the glass down on the books. Slide the mirror half way under the tv. Get the back panel off, and it should look like this:
You will be working in the areas marked 1 and 2. Locate anything you can screw on, with a Philips adjustment head. Sometimes orange, mine were grey. You're trying to locate one called VSCAN, that should be marked on the circuit board, just besides the adjustment head. Mine was of course called Vs, so I assumed (correctly) that I had found it. Mark the adjustment head position with a fine point permanent marker so you can go back to the exact original setting.
Put the screwdriver in the adjustment head, start the TV in HDMI mode and start looking in the mirror to see if the adjustments make any difference. Turn first left, and if left gives more bad dots, turn in the other direction. You should get less of the red dots in the left direction. I turned mine to maximum counter clockwise.
The adjustment head just besides the marked area is some 5-volt adjustment which on my TV does nothing, but if I turn it too much, the TV shuts down, probably as a failsafe against too high voltage.
If you try and adjust this, and the TV shuts down, Don't panic, just disconnect the TV from
the outlet, and wait a minute. Also turn the
adjustment head back to the original position.
Move on to the next circuit board, where you find more adjustments. Mine shows SETUP, SETDN, and a third unmarked. I tried all of them, and all of them correct the red pixel phenomenon to some extent. The SETUP and SETDN are on my TV now one turned to the limit clockwise, and the other one counter clockwise, since those settings gave the best picture. The last unmarked adjustment head did get rid of the last of the red pixels. There was a last grey adjustment head which I didn't tamper with since I was happy with the results. Try these settings on the AV1 channel with a DVD running, so you don't adjust only for HDMI. Shut down the tv for a couple of minutes, start up, and check both channels again, to make any last adjustments.
PLEASE, DO THIS WITH EXTREME CARE SO YOU DON'T GET ELECTROCUTED. WEAR RUBBER GLOVE AND RUBBER SOLED SHOES. DON'T SPILL BEER IN THE TV AND TRY TO WIPE IT CLEAN DURING OPERATION!
Shut down everything, and put it back together.
Good luck!