Hello everyone.
I have an IdeaPad 3-15IIL05 in for repair. The motherboard model is NM-D031. I replaced the board with another NM-D031 unit, but the numeric keypad matrix is completely non-functional (NUM pad keys and NUM lock LED both dead).
Although both motherboards share the same PCB code, the replacement board identifies itself in BIOS as IdeaPad 3-14IIL05, which suggests a different BOM configuration.
During a board-level inspection, I found that the replacement board is missing the following components:
DI4502 (likely part of the keyboard matrix protection/diode array)
RI4504 (keyboard matrix series resistor / pull-line)
These components are present on the original 15IIL05 board.
To rule out firmware mismatch, I dumped and flashed:
the main BIOS
the EC/KBC firmware
from the original 15IIL05 motherboard onto the replacement board.
Despite this, the numeric keypad column/row remains inactive and the NUM LED does not respond.
It appears that the 14IIL05 configuration does not populate the additional keyboard matrix lines required for the 15-inch layout, but I would appreciate confirmation.
Has anyone encountered this issue?
Is the absence of DI4502 / RI4504 part of the 14-inch BOM variant, and is the only fix to populate these components or use a true 15IIL05 board?
I have an IdeaPad 3-15IIL05 in for repair. The motherboard model is NM-D031. I replaced the board with another NM-D031 unit, but the numeric keypad matrix is completely non-functional (NUM pad keys and NUM lock LED both dead).
Although both motherboards share the same PCB code, the replacement board identifies itself in BIOS as IdeaPad 3-14IIL05, which suggests a different BOM configuration.
During a board-level inspection, I found that the replacement board is missing the following components:
DI4502 (likely part of the keyboard matrix protection/diode array)
RI4504 (keyboard matrix series resistor / pull-line)
These components are present on the original 15IIL05 board.
To rule out firmware mismatch, I dumped and flashed:
the main BIOS
the EC/KBC firmware
from the original 15IIL05 motherboard onto the replacement board.
Despite this, the numeric keypad column/row remains inactive and the NUM LED does not respond.
It appears that the 14IIL05 configuration does not populate the additional keyboard matrix lines required for the 15-inch layout, but I would appreciate confirmation.
Has anyone encountered this issue?
Is the absence of DI4502 / RI4504 part of the 14-inch BOM variant, and is the only fix to populate these components or use a true 15IIL05 board?
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