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Power
Failure
The
troubleshooting process always starts with identifying what
works. If the problem is power related (whether battery or a
question of the laptop not turning on) the first step is
establishing that power is getting to the laptop.
This means
checking that the LED on the transformer brick is lit, and
if it isn't (or doesn't have an LED), that it's plugged into
a good power outlet. You can check that by unplugging the
transformer and simply plugging in a lamp. Some of the
oldest notebook models have an internal transformer, so the
line power (110 VAC in the
U.S.,
220 most other places) goes directly into the laptop body.
The next question is whether or not any of the little LED
status lights on the laptop light up with the power plugged
in. Even the oldest models usually have a power good status
light. If you have positive power status and the notebook
simply won't turn on, the next check is the battery. Some
models of notebooks will not operate without a good battery
installed, but most will, so Google up your particular model
with a search like "operating without battery" and find out
if your laptop will operate with a dead or missing battery.
If the battery isn't an issue and the laptop still won't
turn on one with the power good status light lit, it could
be a switch failure, but it's more likely a power regulation
or main board failure. Troubleshooting power regulation or
the motherboard requires test equipment or spare board to
swap out, and is beyond the scope of these articles.
Battery
life is special subset of power problems that has as much to
do with poor designs as actual component failure. The older
NiCd batteries were particularly susceptible to "memory"
issues. If not full discharged after every charging, the
battery cells begin to remember their previous charge level
as a new maximum, and some individual cells may even reverse
polarity while the batteries are being charged. Ni-MH
(Nickel Metal Hydride Battery) which replaced NiCd (Nickel
Cadmium) for standard models are somewhat better, but they
can't fight poorly designed charging circuitry or bad
software controls. All laptop batteries, whatever the shape,
consist of a number of low voltage cells connected in series
to reach the required operating voltages. You can rebuild a
notebook battery (it voids the warrantee :-) but it's
usually not cost effective.
It
pays to go online and read the owners manual for extending
the life of the battery in your particular laptop model if
you didn't do so when you obtained it. Some older notebooks
require that you cycle the battery continually, only working
on AC power for as long as it takes to recharge the
exhausted battery. Many newer models want you to fully
discharge the battery around once a week, but otherwise
don't care about leaving it plugged in the rest of the time,
and newest designs don't care what you do as long as the
laptop actually gets run on battery for a reasonable
percentage of the time. If you think your battery is running
down too fast, make sure you have enabled the aggressive
power saving modes in software (usually accessed through
Control Panel or the manufacturers icon) which dim the
screen, slow the CPU, and let the hard drive spin down when
unused. Also, keep in mind that the level of estimated
battery life remaining that causes an onscreen alarm can be
set by the user, and if your default setting is very
conservative (between 10% and 20%), you may want to
experiment with a lower level (between 3% and 5%) that will
still give you time to save your work and shut down before
the laptop goes into hibernation.
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