Hibernation Mode; Symptom-To-Fru Index - Lenovo ThinkPad T520 Hardware Maintenance Manual

Also, in either of the following events, the computer automatically returns from sleep (standby) mode and
resumes operation:
• The ring indicator (RI) is signaled by a serial device or a PC Card device. ( does not support the ring
indicator (RI) resume by PC Card device.)
• The time set on the resume timer elapses.
Note: The computer does not accept any input immediately after it enters sleep (standby) mode. Wait a
few seconds before taking any action to reenter operation mode.

Hibernation mode

In hibernation mode, the following occurs:
• The system status, RAM, VRAM, and setup data are stored on the hard disk.
• The system is powered off.
Note: If the computer enters the hibernation mode while it is docked to the docking station, do not undock it
before resuming normal operation. If you do undock it and then try to resume normal operation, you will get
an error message, and you will have to restart the system.
To cause the computer to enter hibernation mode, do any of the following:
• Press the Fn+F12 keys.
• If you have defined one of the following actions as the event that causes the system to go into hibernation
mode, perform that action.
- Closing the lid.
- Pressing the power button.
- Pressing Fn+F4 keys.
Also, the computer goes into hibernation mode automatically in either of the following conditions:
• If a "hibernation time" has been set on the timer, and if the user does not do any operation with the
keyboard, the TrackPoint, the hard disk drive, the parallel connector, or the diskette drive within that time.
• If the timer conditions are satisfied in suspend mode.
When the power is turned on, the computer returns from hibernation mode and resumes operation. The
hibernation file in the boot record on the hard disk drive is read, and system status is restored from the
hard disk drive.

Symptom-to-FRU index

This section contains following information:
• "Numeric error codes" on page 40
• "Error messages" on page 41
• "Beep symptoms" on page 42
• "No-beep symptoms" on page 43
• "LCD-related symptoms" on page 43
• "Intermittent problems" on page 43
• "Undetermined problems" on page 44
The symptom-to-FRU index in this section lists symptoms and errors and their possible causes. The most
likely cause is listed first, in boldface type.
.
Chapter 4 Related service information
39