How to Fix a Monitor Broken by Age.

I had an old monitor that stopped displaying images. Signs that this fix may work for you are;

*Still connects and is detectable

*"On" light flashes rather than staying on.

*Display doesn't turn on. (This won't fix cracks)

With these symptoms, it's likely that the capacitors in your monitor have gone bad for some reason or another. Mine was an old monitor, so I'm assuming that they did because of electrolytic breakdown over age. They don't last forever.

Luckily, it's a fairly easy fix for someone with a little time on their hands and access to basic soldering/desoldering equipment.

So with that, let's fix that monitor!

• Old, non-functioning monitor you wish to fix
• Phillips and Flathead Screwdrivers (Might need specialty if your monitor requires it)
• Ability to order parts (Or a varied supply of capacitors on hand)
• Solder Iron
• Solder Sucker (Or desoldering iron like I have access to)
• Solder + Flux
• Wire Cutter

First up, you've got to safely get to the circuits. (Without damaging your monitor further)

Every monitor is going to be different, so the locations are going to be different; but this monitor I simply looked for screws on the back, removed them and then carefully pried apart the case.

*It's a good idea to take pictures as you go along and carefully document or keep isolated what goes where. I used small plastic baggies to keep screws/parts for each stage separated.

There's usually tabs on the sides that *snap* in. If needed, use your flathead screwdriver to apply pressure and undo these snaps.

Don't force anything. It may require some finagling, but it should come apart without much pressure. If it's stuck, then look along that edge to see if one of those snaps is there and try pulling or applying pressure at a different angle.

When in doubt, google "(Your monitor model) case removal" and hopefully you'll find some answers.

Now that the outer case is off, it's time to isolate the circuits.

*Note; if you want to be extra careful, you should ground yourself with a grounding strap before touching the PC boards. Static electricity can damage circuits. *

Go around the outside of the shield and look for connecting points. Disconnect any wires you may find.

For this monitor, the shield (Sheet metal case the electronics are mounted inside of) was just sitting on the back-light. Make note of how the wires lay and then take it off and flip it around.

Remove screws from PC boards (Circled in red) and remove PC boards from shield. Be mindful of any more connectors (Wires and monitor cable posts in my case) that may need to be disconnected.

Set aside PC boards on a non-conducting surface. (I used granite)

The next step now that you have the PC boards isolated, is to figure out which capacitors, or "caps" for short are the likely culprit.

Luckily, it's usually easy to diagnose and can be discernable with the naked eye due to "bulging" capacitors.

These bulges are created when the capacitor is subjected to voltage/current outside of it's range. It usually doesn't happen in newer devices, but over time the electrolyte in the capacitor breaks down and it's operating range changes. Too much time and the standard variables for the monitor will be outside of the capacitor's range and it fails, causing a bulge.

*Note; this is off the top of my head + a quick google search to verify. If this explanation is wrong, please correct me and I'll edit it.

Once you've identified the culprit, look for it's values on the side of the capacitor. In particular, we're looking for Voltage (V) and Capacitance (uF).

For the bulging capacitor in this example, it wound up being "25V 1000uF".

Since they're fairly cheap, I decided to replace ALL of the aluminum "can" type capacitors on this board with the assumption that the others are probably not very far behind the already bulging one on their way to failure.

*Note: There were none of this type of capacitor on the green board, so I decided to just leave that one alone.

There are plenty of websites that sell replacement electronic parts. For this example, I used Digikey with the following steps:

1. Type the type of part you need in the search bar (Capacitor)
2. Specify sub-type (Aluminum Electrolytic)
3. Navigate to the values you require. (50V, 1000uF)
4. Pick one from the list. (+-20% is a middle of the road value for tolerance; and I got all mine from the same brand although I don't think that matters)
5. Set quantity and add to cart

Rinse and refresh for however many you're getting. You don't *have* to replace them all. But I'd rather not have to do this twice so I went ahead and did so.

While waiting for my parts to show up, I set aside the monitor carefully in it's disassembled state where it won't be bothered.

This is usually the hardest step. (For me)

We're going to de-solder and remove the capacitors you wish to replace.

First, pick a capcitor and note it's orientation. In particular the white stripe on the side designates polarity, make sure your replacement orientation matches. (I started with the big one and worked my way down)

Then locate it on the reverse side. It won't always be the case, but in my example the PC board was labeled on both sides. Was really easy to just check the letter/number combo and verify I had the right spot.

Next, heat up the solder joint. With mine I used a de-soldering station which had a built in solder sucker. I set the temperature to 330 F and tested it, increasing the temperature until I got a good melt. With this board, it needed to be a little on the high side at 380 F, but that may have been an inaccuracy with the station.

Then just put the tip around the bead and push the button once it's melted; a vaccuum activates and sucks out the melted solder.

You CAN do this with just a regular iron and solder-sucker though. It's the same process where you heat up the bead but you'll have to manually bring the nozzle to the melted solder and push the switch, sucking it up in one motion. This is a bit trickier to do and I vastly prefer the convenience of the desoldering station. (Bonus points if your work lets you use theirs like mine)

Whichever you use, it's a good idea to clean your iron with a damp cloth, sponge or copper wool to keep the tip functioning.

Then remove the capacitor. This one had some glue on it, so I wiggled it a bit to break it free. Be careful, be patient and try not to break the PCB as that'll end the project quick.

I'd advise only removing one capacitor at a time if you're doing multiple like me. Makes it easier to remember what goes where.

Next up it's time to replace that capacitor!

Find your replacement from the new ones. The values are usually listed on the bag, but I like to hold them up side-by-side to compare and be sure.

Then place the new one in the old location, making sure that the orientation is correct. This PCB had markings designating which side the silver line (negative) should be on, so keep an eye out for those.

Then add just a dab of flux onto the lead to ensure propper adhesion. The flux chemically cleans the weld location and allows for better "wetting" of the joint. In my picture, I overdid it slightly but it wasn't a problem.

Then move on and do it again for each part you have.

*Be really careful that you don't get any splatter or solder where it's not supposed to be. If you accidentally create a bridge it can cause a short and ruin components.*

When you've completed these steps for every piece it's time to snip the unused portion of the posts and you're done with this stage!

Go in the reverse order as disassembly, making sure that wires are reconnected, screws are tightened (Firm, but not forced) and parts are replaced until your monitor is back together.

Those snaps on the enclosure should be a snap, just apply pressure until you hear them engage. (Or they're firmly in place)

The last thing to do is plug it in!

If you've done everything correctly and have a little luck, it should start up and display just like normal.

Enjoy your repaired monitor!