Lenovo ThinkCentre 0401, Hardware Maintenance Manual, Page: 78 / 170

POST error codes
Each time you power-on the system, it performs a series of tests that check the
operation of the system and some options. This series of tests is called the
Power-On Self-Test , or POST . POST does the following operations.
v
Checks some basic system-board operations
v
Checks the memory operation
v Starts the video operation
v
Verifies that the boot drive is working
If the POST detects a problem, an error message appears on the screen. A single
problem can cause several error messages to appear. When you correct the cause of
the first error message, the other error messages probably will not appear on the
screen the next time you turn on the system.
POST Error Message Description/Action
CMOS battery failed The CMOS battery is no longer functional.
Replace the battery.
CMOS checksum error - defaults loaded Checksum of CMOS is incorrect.
The computer loads the default
configuration settings. This error might
indicate that CMOS has become corrupt due
to a weak CMOS battery.
CPU at nnnn nnnn is the running speed of the
microprocessor.
Press Esc to skip memory test Pressing Esc skips the full memory test
HARD DISK INSTALL FAILURE Cannot find or initialize the hard disk drive
controller or the drive.
Make sure the hard disk drive is correctly
installed.
If no hard disk drives are installed, make
sure the hard disk drive selection in Setup is
set to NONE.
Keyboard error or no keyboard present Cannot initialize the keyboard.
Make sure the keyboard is properly
connected to the computer and that no keys
are held pressed during POST.
To purposely configure the computer
without a keyboard:
1. Start the Setup Utility program. See
“Starting the Setup Utility program” on
page 45.
2. Select Startup
→
Keyboardless Operation
→ Enabled .
Memory Test: This message displays during a full memory
test, counting down the memory areas being
tested.
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Hardware Maintenance Manual