Post Error Codes; Undetermined Problems - Lenovo H520s Hardware Maintenance Manual

POST error codes

Each time you turn the computer on, it performs a series of tests to check that the system is operating
correctly and that certain options are set. This series of tests is called the Power-On Self-Test, or POST.
POST does the following:
• Checks some basic system-board operations
• Checks that the memory is working correctly
• Starts video operations
• Verifies that the boot drive is working
POST Error Message
Keyboard error
Reboot and Select proper Boot device or Insert Boot
Media in selected Boot device

Undetermined problems

1. Power-off the computer.
2. Remove or disconnect the following components (if connected or installed) one at a time.
a. External devices (modem, printer, or mouse)
b. Extended video memory
c. External Cache
d. External Cache RAM
e. Hard disk drive
f. Disk drive
3. Power-on the computer to re-test the system.
4. Repeat steps 1 through 3 until you find the failing device or component.
If all devices and components have been removed and the problem continues, replace the system board.
20
Lenovo H520sHardware Maintenance Manual
Description/Action
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, select Keyboardless
operation in Startup option to Enabled. The BIOS then
ignores the missing keyboard during POST.
The BIOS was unable to find a suitable boot device. Make
sure the boot drive is properly connected to the computer.
Make sure you have bootable media in the boot device.