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If Something Goes Wrong

Power and the batteries

5Check for the error again.
6If the error recurs, remove the memory module entirely and
check for the error again.
If removing the memory module eliminates the error, the
memory module may be faulty. If the error recurs without the
memory module installed, the error is not caused by the
memory module.
TECHNICAL NOTE: You must have at least one memory module
installed for the computer to work.
Power and the batteries
Your computer receives its power through the AC adaptor and
power cord/cable or from the system batteries (battery and real-time
clock (RTC) battery). Power problems are interrelated. For
example, a faulty AC adaptor or power cord/cable will neither
power the computer nor recharge the batteries.
Here are some typical problems and how to solve them:

The AC power light does not come on when you plug in the

AC adaptor and power cord/cable.

Make sure the AC adaptor and power cord/cable are firmly plugged
into both the wall outlet and the computer.
If the AC power light still does not come on, check that the wall
outlet is working properly by plugging in a lamp or other appliance.

The AC adaptor and power cord/cable work correctly, but the

battery will not charge.

The battery does not charge while the computer is consuming full
power. Try turning off the computer.
The battery may not be inserted correctly in the computer. Turn off
the computer, remove the battery, clean the contacts with a soft dry
cloth (if necessary) and replace the battery. See “Removing the
battery from the computer” on page 86.
The battery may be too hot or too cold to charge properly. If you
think this is the probable cause, let the battery reach room
temperature and try again.
If the battery has completely discharged, it will not begin charging
immediately. Leave the AC adaptor and power cord/cable
connected, wait 20 minutes and see if the battery is charging.