Repair your electronics by replacing blown capacitors

Checking for blown capacitors in your malfunctioning electronics is fast and easy if know what you're looking for. Replacing one part at a couple dollars a piece is much cheaper than replacing an entire monitor for hundreds of dollars! Monitors, digital converters, and other video- related electronics commonly have power issues that are caused by faulty (read: low quality production) capacitors. Common symptoms include:

- Unit won't turn on
- Unit won't return from standby
- Unit turns on and off intermittently
- Screen flickering or distorted
- Lines across the screen

If you're experiencing any of these, it's worth taking several minutes to check your circuit board capacitors.

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Step 1: Tools needed

Checking the capacitor just requires your eyeballs but replacing them requires a few tools:

- Screwdriver, hex wrench, or whatever's needed to open the case
- Soldering iron
- Replacement capacitors (you will find the values for this in the following steps)

Also optional but helpful is soldering wick, which is available for fairly cheap at Radio Shack.

In this example I'm repairing a digital TV converter box that will power on, but does not activate from standby.

raptor402 says: Mar 18, 2013. 3:54 AM

Hello, sir/ma'am

Your instructable is wonderful. I have a question: I have an XBox 360 slim with a 100-127v input power supply. In my country, the wall outlets are all 220v, so I was using a step-down transformer with the console. Unfortunately, I tried out a smaller converter without reading that it was not transformer based. To sum it up, there was a bang and some smoke.
I opened up the adapter and found that one big capacitor had burst open (that was my first guess as I had seen a capacitor burst with my own eyes, and that was my own doing) and the electrolyte was spread around. I cleaned up the electrolyte and tried the adapter. The console would work for a minute and then shut down, implying that the rest of the adapter is function.
My question is: will replacing the capacitor fix the adapter and make it usable again?

rbennett8 says: Sep 3, 2012. 6:14 PM

i can vouch for this i had o recently recap my 26" lcd tv due to it turning on and off intermittently

i recommended this site they will help you out a lot with the process

http://www.badcaps.net/

http://www.badcaps.net/forum/

also the desoldering wick from radio shack from my experience is junk

this one is good i have not had a problem with it yet
http://www.drillspot.com/products/1429031/Tech_Spray_1811-5F_Desoldering_Wick?s=1

crowman73 says: May 15, 2012. 12:24 AM

I'll definitely use this tip in future, thanks.

nickmccullough says: May 13, 2012. 9:23 AM

thank you sir, very helpful.

i had a DVD player stop working, turns out it blew the switching power supply IC, and a fuse as well. I replaced them and the unit still didnt power on.

i had overlooked a couple of blown caps, so thanks for reminding me to take a second look! all is functioning well

Dr.Bill says: May 13, 2012. 2:49 AM

I always suspected the tops of the caps were scored for a reason.

Horsehockey says: May 12, 2012. 7:23 AM

You say to note the polarity of the capicator. Trying to determine the polarity of capicators, especially on well pump motors or other outside erquipment, has always baffled me. Maybe the little blue capicators have the polarity on them.
I have asked many highly intelligent electronics technitians how to determine if a capacitor was bad. Their reply was that if they thought it could be bad they replaced it. You are the first person I have seen that has come up with a simple way to dewtermine a bad capicator. Thanks for sharing.

fhidiort (author) in reply to HorsehockeyMay 12, 2012. 10:23 PM

Usually electrolytic capacitors have a stripe with minus signs down the side that indicate the negative lead. You can see in the Step 5 picture the blue capacitor has a black stripe with blue minus signs- that's the negative end. Also on some circuit boards (including the one used in this example) the polarity is marked on the board itself with a little plus and minus sign.