Lenovo B570e Notebook - Manual (Page 39)

Sleep or hibernation problems
Problem Solution
The critical low-battery error message appears, and the
computer immediately turns off. The battery power is getting low. Connect the ac power
adapter to the computer, or replace the battery with a
fully charged one.
The computer enters sleep mode immediately after
Power-on self-test (POST). Make sure that:
• The battery is charged.
• The operating temperature is within the acceptable
range. See “Use and care information” in the Safety
and Warranty Guide that comes with your computer.
Computer screen problems
Problem Solution
The screen is blank. • Do the following:
– If you are using the ac power adapter, or using the
battery, and the battery status indicator is on, press
Fn+up arrow to make the screen brighter.
– If the power indicator is in blinking, press the power
button to resume from the sleep mode.
– If the problem persist, follow the solution in the
following problem “The screen is unreadable or
distorted.”
– Press Fn+F2 to confirm whether the LCD screen has
been turned off.
The screen is unreadable or distorted. Make sure that:
• The display device driver is installed correctly.
• The screen resolution and color quality are correctly
set.
• The monitor type is correct.
Incorrect characters appear on the screen. Did you install the operating system or application
program correctly? If they are installed and configured
correctly, have the computer serviced.
Sound problems
Problem Solution
No sound can be heard from the speaker even when the
volume is turned up. Make sure that:
• The mute function is off.
• The headphone jack is not used.
• Speakers are selected as the playback device.
Chapter 5 . Troubleshooting 25