This instructable will show you how to diagnose and repair bad
capacitors on computer circuitry saving you money on new appliances and
preventing landfills from filling up.
WARNING RISK OF ELECTRICAL SHOCK CONTINUE AT YOUR OWN RISK
Always unplug electronic devices before opening them! Even after
opening make shore you discharge all the capacitors with a discharge
rod.
It is difficult to get a piece of technology to work as good as it
used to, once it's broken. Which is why most 'repair' procedures stay
with hardware enthusiasts, because the best option for most other
consumers is to replace it. With that in mind, we look at the resources
that we have and try to get the best out of it.
The motherboard
is located inside the cabinet and consists of a microprocessor, chipset
and BIOS (Basic Input/Output System). The microprocessor decides the
type of Central Processing Unit (CPU). The chipset constitutes two
bridges: the north bridge and south bridge. These bridges control the
flow of data in the computer. The basic functioning of the computer is
controlled by the BIOS, which is a real-time clock and a major component
of the motherboard. The slots and ports on it connect the computer
peripherals like the sound card or graphics card. These slots provide a
connection between the hard disk and the computer peripherals.
Troubleshooting a Bad Motherboard
Hardware
diagnostics can be a pure pain in the ass. There is literally too much
going on in there to efficiently dissect the faulty stuff and repair it.
This is why most repair work is usually done by professionals or
hobbyists. It takes a long time to get a full grip on handling hardware
issues with precision. That said, there are a few common problems with
pretty easy solutions as well. Let's have a look at the MoBo
(motherboard) itself for any repair options.
Replacing Capacitors
The
constant problem of popping capacitors is well-known by professionals
and enthusiasts alike. Capacitors are the first thing to blow in a
well-built electronic unit. The problem persists wherever a capacitor is
used (commonly called the 'Capacitor Plague'). The only option to this
is to replace the capacitor with a new one. Spotting a bad capacitor is
easy: it's the one with the bulging top and leaking electrolytic goo.
Most capacitors expel the electrolytic fluid inside them. It either
dries up on the outer part of the top of the capacitor or leaks on to
the circuit board. Worst-case scenario, the capacitor explodes due to
too much electrical stress. If you see no damage on them, you can still
check them using a capacity gauge or a multimeter.
To replace the capacitors, you will need:
a program-controlled soldering station with both soldering and de-soldering irons,
genuine capacitors of the same capacity as the old ones and
experience in soldering and knowledge of the risk involved.
Because
one false move and you'll damage the internal circuitry of the board
and lose the board completely. You have to de-solder the pins from under
the board, take the dead capacitor out, put the new one in and solder
the pins back; all in one shot. You need to be extremely cautious about
the polarity of the capacitor. If you put it in the wrong way, the
capacitor pops almost as soon as you power it up.
Motherboard Component Diagnosis
POST Check With Beep Codes
To
diagnose a problem, you need to know where to look. The first stop
would be the BIOS POST (Power-On Self-Test). If your computer (not your
speakers, your cabinet) makes beeping sounds when you start it up, it
means there is a problem with certain part/s on the MoBo. This is good
(relatively speaking) because the beeps will directly tell you what's
wrong. Pay close attention to the kind of beeping sound (the duration -
short or long and the number of beeps). Search online for the 'computer
beep code' and you should have found out which component is faulty. This
will only work if the parts are on the verge of going down. If
something does go down, your computer probably wouldn't start and you'll
have to figure out the problem manually.
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