Lenovo 4220, 4222, 4215, 4219, 4221 manual POST error codes

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-OnSelf-Test, or POST. POST does the following operations.

•Checks some basic system-board operations

•Checks the memory operation

•Starts the video operation

•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,
	set the error halt condition in Setup to HALT ON ALL, BUT
	KEYBOARD. The BIOS then ignores the missing keyboard
	during POST.
Memory Test:	This message displays during a full memory test, counting
	down the memory areas being tested.
Memory test fail	If POST detects an error during memory testing, additional
	information appears. This information gives specifics
	about the type and location of the memory error.

64Hardware Maintenance Manual