Debug Code LED
The Debug Code LED displays progress and error codes during and after POST. Refer
to the Debug Code LED table for details.
Hexadecimal Character Table
Hexadecimal
0
Debug Code
0 1 2 3 4 5 6 7 8 9 A B C D E F
LED display
Boot Phases
Security (SEC) – initial low-level initialization
Pre-EFI Initialization (PEI) – memory initialization
Driver Execution Environment (DXE) – main hardware initialization
Boot Device Selection (BDS) – system setup, pre-OS user interface & selecting a
bootable device (CD/DVD, HDD, USB, Network, Shell, ...)
Debug Code LED Table
SEC Progress Codes
01
Power on. Reset type detection (soft/hard)
02
AP initialization before microcode loading
03
System Agent initialization before microcode loading
04
PCH initialization before microcode loading
06
Microcode loading
07
AP initialization after microcode loading
08
System Agent initialization after microcode loading
09
PCH initialization after microcode loading
0B
Cache initialization
Debug Code LED
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
Onboard LEDs
47