Apparently this is a common problem with LCD computer monitors, where the monitor will turn on, but only display a screen for about 1 to 2 seconds. Shining a flashlight onto the screen will reveal that the image is there, but the backlight is off. With research I found one or two capacitors in the power supply may have gone bad.

Anyone with basic electrical & soldering skills should be able to perform this repair, as $3.50 is cheaper than buying a new monitor.

My monitor is a Rosewill R710E but this fix works on a wide range of monitors. Please use common sense when working with electricity & soldering irons. I will take you step by step on how to fix your unit.

Items Needed.
• Your Monitor
• Soldering Iron
• A phillips & flat screwdriver
• One 1,000-microfarad, 16-volt polarized capacitor
• One 470-microfarad, 16-volt polarized capacitor

1 Disassemble Monitor

Have a clean well lit work area and remove the back cover. There are a number of screws around the outer edge of the back cover. Once you remove those, you’ll need to gently pry around the edges of the cover with the flat screwdriver to pop it off.

Once the back cover is removed, you will see a metal shroud covering the electronics. There are a few screws holding this down as well. Remove the screws and then slide the shroud slightly to the right to remove it.

NOTE: There is a black cable running from the monitor’s control panel into the shrouded area. You’ll need to remove the small screw grounding it to the monitor chassis to unplug it from the circuit board under the shroud.

2 Locate Problem Capacitors

There are two capacitors you are looking for, both on the main (left-side) power supply circuit board. There is a yellow transformer near the top of the board; one of the capacitors will be above it, and the other will be slightly to its left. One is part number C924 (1,000 mfd 16v) and the other is number C922 (470 mfd 16v). One or both capacitors should have a slightly bulging top. If not this fix may not work for you.

3 Replace Problem Capacitors

Remove the defective capacitor(s) and install the new capacitor(s). You’ll need to use your soldering iron to remove the old ones, from the bottom of the board.

There are several screws holding the board down. Be careful when removing the board so as not to damage the two connectors attaching it to the green video board. You should have enough solder still on the board to re-attach the new capacitors; if not, you can use a little more solder.

Remember, when replacing capacitors, always use the same microfarad value and the same or higher voltage. For instance replacing a 1,000 mfd 16v capacitor with a 1,000 mfd 35v should be no problem. Be sure to install the capacitors with the correct polarity, just as you would with a battery. The wide gray or white band on a capacitor is the negative side. The positive side is marked on the board.

I obtained my new capacitors from Radio Shack locally. I bought both a 470uF 35V Catalog#272-1030 & a 1000uF 35V Catalog#272-1032 RADIAL lead capacitor. Cost was about $3.50

4 Reassemble Monitor

Replace the power supply board, metal shroud and back cover. Make sure that when you replace the board, the two connectors attach to the video board. Remember to reconnect that black cable to its connector on the bottom of the video board as well. The metal shroud slides into place as before. Snap down and screw on the back cover, and you’re done! I hope this fix works for you as well as it did for me.

To prevent electric shock always make sure that any equipment you plan on opening up is unplugged . The area you will be working in on this monitor carries active high voltage when it is plugged in.

Always remember to install capacitors with correct polarity. Putting them in backwards will damage them and could damage your monitor.

You should wear long pants and sleeves to prevent accidental burns if you are inexperienced with a soldering iron. Always replace the tip into its holder when not in immediate use.

Buy me a drink!

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