Hibernation Mode; Symptom-To-Fru Index - Lenovo 20YG00CAIX Hardware Maintenance Manual

• The ring indicator (RI) is signaled by a serial device or a PC Card device.
• The time set on the resume timer elapses.
Note: The computer does not accept any input immediately after it enters sleep 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 drive, hybrid drive, or solid-
state drive.
• The system is powered off.
Note: If the computer enters the hibernation mode while it is docked to the docking station or the port
replicator, 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.
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.
Also, the computer goes into hibernation mode automatically after a period of inactivity specified in power
plan settings.
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, hybrid drive, or solid-state drive is read, and system
status is restored from the hard disk drive, hybrid drive, or solid-state drive.

Symptom-to-FRU index

This section contains following information:
• "Numeric error codes" on page 36
• "Error messages" on page 37
• "Beep errors" on page 37
• "No-beep symptoms" on page 39
• "LCD-related symptoms" on page 39
• "Intermittent problems" on page 40
• "Undetermined problems" on page 40
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.
Note: Do the FRU replacement or other actions in the sequence shown in the column headed "FRU or
action, in sequence." If replacing a FRU does not solve the problem, put the original part back in the
computer. Do not replace a nondefective FRU.
This index can also help you determine, during regular servicing, what FRUs are likely to need to be replaced
next.
A numeric error is displayed for each error detected in POST or system operation. In the displays, n can be
any number.
.
Chapter 4 Related service information
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