I need to know how to clean the LG flatron L1953T screen without damaging it in any way? should we just used windex or not? it has been wiped with a damp cloth and now has water marks.

Windex is not the best cleaner. Bed and Bath Beyond has a very good NON-Streak class cleaner that I tell my customers to use. The best solution is NOT to Spray directly onto the TV Screen. Remember the glass is only delivering the picture from an RGB projection unit sitting inside the enclosure. It is not the electronic projector and the screen is separate. It can be replaced if damaged; however I believe it is only streaked and needs proper cleansing. If you get the new cleaner, spray the solution onto a soft cloth and wipe the exterior screen. Promptly wipe it dry and if you need to do this a few times, eventually you will get the glass clear and enjoy the show.

try diffrent cable

Use a fine rag and water ONLY. Windex will ruin it.

Any glass cleaner without Amonia, I use screen cleaner from Radio Shack, apply it to the micro fibre cloth and wipe the screen gently.
http://s807.photobucket.com/home/budm/allalbums

It depends on the kind of dirt you've got on the LCD screen.

Dust and fingerprints may be safely removed using a tissue-non-tissue or microfiber cloth, sold in most camera shops. It's exactly the same supplied with most glasses, only bigger. It works without moistening. Do not press overmuch, but wipe it repeatedly, and even the sturdier fingerprint WILL come away eventually.

There are also specially formulated moist-wipes. They're more expensive and only good for one use each, but are good to clean dried spills such as specks of sugared coffee or an explode-on-open Coca Cola can. You'll find them in most computer shops.

just connect the power cable to the monitor if you see a test page or any thing on the screen the monitor is ok if not the monitor may be bad , usually monitor has a three year warrenty check it also repairs are usually very expensive on it .

Did you inspect the caps, any bulging one? Measure the power supply to see if you do have 5v and 12v on the power supply/inverter board.
See pictures and websites so you will know what to look for:
http://s807.photobucket.com/home/budm/allalbums
http://en.wikipedia.org/wiki/Capacitor_plague
http://www.badcaps.net

Proper cleaning of a Touchscreen

1. Step 1 Turn off both the computer and touch screen. This way, you can see everything that needs to be cleaned. Some touch screen applications has a cleaning mode which turns off the screen for the specific purpose of cleaning. However, the monitor's brightness can make you miss some areas.
   
2. Step 2 Wet a soft, lint-free or microfiber cloth with distilled water. Wring out as much water as you can. Make sure the cloth is damp but not wet. Wipe the screen in a gentle motion to remove dust, oil, or fingerprint smudges off.
   
3. Step 3 Another option is to use a screen cleaner kit that includes antistatic wipes. You can buy this at various electronic or online stores. Spray a little solution on a wipe then rub it gently across the screen.
   
4. Step 4 Finish cleaning the touch screen with a dry lint-free cloth to wipe any excess moisture, then turn it back on.
   

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Take a clean cloth and spray some windex on the cloth and then wipe down the screen and it should come nice and clean. Never spray it directly on the screen cause if the liquid goes down inside of the screen then it could damage it.

I just bought a 42" lg hdtv very nice but had a big spoto in the middle of the screen. I used windex wipes to clean the screen and it is good as new again!! Hope this helps!!