Monitor Revival

Two years ago, my 19 inch LG flat-screen computer monitor died. I immediately went to my local hhgregg store and upgraded to a 23 inch LED/LCD widescreen monitor. It was so much better I kind of wished the old monitor had died sooner. I stashed the defunct monitor in my junk room, thinking I would fix it one day. My recent success with repairing my TV (see HDTV Action) inspired me to get off the dime and have a go at repairing the monitor.

The problem is the monitor won’t turn on unless the temperature is above 85° F. Even the power-on LED stays dark. Above 85° it works fine. I reckoned the cause had to be in the power supply and was probably more bad electrolytic capacitors.

Only seven screws hold the unit together, but after removing them the front bezel remained firmly attached to the back of the unit. It turned out they were held together by little “snaps” molded into the bezel. Using a thin screwdriver blade and my fingers, I was able to pry apart the front and the back.

	The “guts” of the monitor are shown at left. The large metal panel holds the LCD display and the CCFL (cold cathode fluorescent lamps). The small box holds the power supply and controller electronics.
	After flipping the small box over and removing a plastic panel, the power supply board is visible on the right.
	The power supply contains a half dozen electrolytic capacitors. Two of them have swelled but have not vented electrolyte. The two bad capacitors are at the bottom right and center right of the photo. One is rated 1000µF/16VDC and the other is rated 680µF/25VDC.
	I drove to Radio Shack and bought two 1000µF/35VDC electrolytic capacitors. The photo at left shows them installed in place of the bad caps. The monitor now works normally. HDTV repaired: check. Computer monitor repaired: check. Stand aside, I’m on a roll!