Lenovo E43 User Manual page 61

If the sleep indicator is on, your computer is in sleep mode. Connect
the AC adapter to the computer, then press any key or the power
button.
If the sleep indicator is off, your computer is in sleep/hibernation
mode or power-off state. Connect the AC adapter to the computer;
then press the power button to resume operation.
If the system still does not return from sleep mode, your system has
stopped responding, and you cannot turn off the computer; reset the
computer (unsaved data may be lost). To reset the computer, press and
hold the Power button for 4 seconds or more. If the computer is still not
reset, remove the AC adapter and the battery.
Computer screen problems
The screen is blank.
Do the following:
If you are using the AC adapter, or using the battery, and the battery
status indicator is on, press Fn +
If the Power indicator is in blinking, press any key or the Power button
to resume from the sleep mode.
If you still have the problem, do the Solution in the following problem
"The screen is unreadable or distorted."
Chapter 4. Troubleshooting
to make the screen brighter.
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