Lenovo IdeaPad Y400 User Manual page 32

Chapter 4. Troubleshooting
Sleep mode problems
The critical low-battery error
message appears, and the
computer immediately turns off.
The computer enters sleep mode
immediately after Power-on self-test
(POST).
Note: If the battery is charged and the temperature is within range, have the computer serviced.
The computer does not return from
sleep mode and the computer does
not work.
Display panel problems
The screen is blank.
The screen is unreadable or
distorted.
Incorrect characters appear on the
screen.
Audio problems
No sound can be heard from the
speaker even when the volume is
turned up.
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The battery power is getting low. Connect the AC adapter to the
•
computer, or replace the battery with a fully charged one.
• Make sure that:
- The battery is charged.
- The operating temperature is within the acceptable range. See
"Chapter 2. Use and care Information" of Lenovo Safety and General
Information Guide.
• If your computer is in sleep mode, connect the AC adapter to the
computer, then press any key or the power button.
• If the system still does not return from sleep mode, stops
responding, or you cannot turn off the computer, please 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.
• Do the following:
- If you are using the AC adapter, or using the battery, and the
battery status indicator is on, press Fn + ↑ to make the screen
brighter.
- If the power indicator is in blinking, press the power button to
resume from Sleep mode.
- If the problem persists, follow the solution to the following
problem "The screen is unreadable or distorted."
- Press Fn + F2 to confirm whether the LCD screen has been turned
off.
• Make sure that:
- The display device driver is installed correctly.
- The screen resolution and color quality are correctly set.
- The monitor type is correct.
• Are the operating system or programs installed correctly? If they are
installed and configured correctly, have the computer serviced.
• Make sure that:
- The Mute function is off.
- The headphone jack is not used.
- Speakers are selected as the playback device.