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Troubleshooting guide
Problem
Cause and action
All or some keys on the
external numeric keypad
do not work.
Make sure that the external numeric keypad is correctly connected to the
computer.
All or some keys on the
external keyboard do not
work.
To use an external keyboard, you need to attach the keyboard/mouse cable to
the computer. Make sure that:
The keyboard/mouse cable is correctly connected to the computer.
The keyboard cable is connected to the correct side of the keyboard/mouse
cable.
If these items are correct, disconnect the keyboard/mouse cable from the
computer and make sure that the operation of the system keyboard is correct. If
the system keyboard works, have the keyboard/mouse cable or the external
keyboard serviced.
Suspend or hibernation problems
Problem
Cause and action
The computer enters
suspend mode
automatically.
The computer enters suspend mode automatically when the processor
temperature reaches a certain level. This is not a defect.
The computer enters
suspend mode
immediately after POST
(the suspend indicator
turns on).
Make sure that:
The battery pack is charged.
The operating temperature is within the acceptable range. Refer to
Appendix A.
If these items are correct, have the computer serviced.
Error
19ð
appears, and
the computer immediately
powers off.
The battery power is getting low. Connect the AC Adapter to the computer, or
replace the battery pack with a fully charged one.
The LCD is blank after
resuming.
Check if an external monitor was disconnected while the computer was in
suspend mode. Do not disconnect the external monitor while the computer
is in suspend mode or hibernation mode. If no external monitor is
attached when the computer resumes, the LCD remains blank and output
is not displayed. This restriction does not depend on the resolution value.
The computer does not
return from suspend
mode, or the suspend
indicator stays on and the
computer does not work.
The computer automatically enters suspend or hibernation mode when the
battery power is empty. Do one of the following:
Replace the battery pack with a fully charged one, and then press Fn.
Connect the AC Adapter to the computer; then press Fn.
Chapter 4. Solving computer problems
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