Replacing a capacitor on a motherboard is a very
detailed process and takes a steady hand to achieve. Each capacitor is
attached to a motherboard very precisely, using solder. When you replace one, the same precision must be used or you risk permanent damage to your machine.
Locate the defective capacitor
The
first step in the repair process is to identify the capacitor that
needs to be replaced. Typically, a bad capacitor has some manner of
bulge on the top of it. Bulges are sometimes very subtle which makes
them difficult to detect. Another sure sign that a capacitor is bad, is
if it has leaked.Remove the damaged capacitor
The junction point for each capacitor is on the bottom of the motherboard, so you need to remove the motherboard
to access the underside. Using your soldering iron, heat the existing
solder at the junction point for each (usually two total) leg of the
capacitor. Then, gently pull the capacitor away from that leg on the top
side of the motherboard.
Tip: If you run into any issues
melting the existing solder on the motherboard, try adding a little bit
of new solder, then heating them together.
Replace the old capacitor
After removing the bad capacitor, you must clean the
holes before you can put a new one in place. This is achieved by heating
the leftover solder in the holes and using a "solder sucker" to remove
any excess. When the holes are clean, you can proceed with installing a
new capacitor. There is a positive and a negative leg on each capacitor,
so you need to make sure you insert the legs through their
corresponding holes in the motherboard. The motherboard should have
markings to indicate which hole is positive and negative.
Tip: The positive leg, or terminal, is typically a little longer than the negative one.
After
you have inserted the capacitor legs into the correct holes, clip off
the excess wiring from each leg. Clip them to the length of about two
millimeters from the underside of the motherboard.
Now you can apply fresh solder at each junction point. You should only
need a drop of solder to secure the leg at each junction point. The bad
capacitor is now replaced and you can test out the motherboard to see if
it works properly again.
Caution: Make sure the new solder DOES NOT TOUCH any of the existing solder at another junction point as this could cause circuits to cross and short out the motherboard.
