Lcd-Related Symptoms - Lenovo ThinkPad X1 2-in-1 Gen 9 Hardware Maintenance Manual

Table 3. No-beep symptoms (continued)
Symptom or error
No beep, power-on indicator on, LCD blank, and LED
indicators on Esc, F1 and F4 blink during POST.
The NVMe password prompt appears.

LCD-related symptoms

Important: The TFT LCD for the notebook computer contains many thin-film transistors (TFTs). The
presence of a small number of dots that are missing, discolored, or always lighted is characteristic of TFT
LCD technology, but excessive pixel problems can cause viewing concerns.
If the LCD you are servicing has two or less visible defective pixels, it should not be considered faulty.
However, if the LCD has three or more visible defective pixels, it will be deemed as defective by Lenovo and
it should be replaced.
Notes:
• This policy applies to all ThinkPad Notebooks purchased on 1 January, 2008 or later.
• Lenovo will not provide warranty replacement if the LCD is within specifications because we cannot
guarantee that any replacement LCD will have zero pixel defects.
• One pixel consists of R, G, B sub-pixels.
LCD Self Test
When you turn on the computer and the LCD goes black, run LCD Self Test to help you determine whether
the LCD functions normally.
To run LCD Self Test:
1. Ensure that the computer is connected to ac power. Then, press the power button for about seven
seconds to turn off the computer.
2. Press Fn, left Ctrl, and the power button at the same time. If the computer displays five solid colors in
sequence across the entire screen, it indicates that the LCD functions normally.
3. The test lasts for about 20 seconds and then exits automatically. You also can press the power button to
exit the test.
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ThinkPad X1 Carbon Gen 12 and ThinkPad X1 2-in-1 Gen 9 Hardware Maintenance Manual
FRU or action, in sequence
UEFI BIOS is self-recovering. If the UEFI BIOS is
corrupted or maliciously attacked, it can self-recover and
restore computer from the last uncorrupted and secure
backup.
The blinking LED indicators on keys indicate the self-
recovery progress:
• LED indicator on Esc blinks: 0% to 32%
• LED indicators on Esc and F1 blink simultaneously:
33% to 65%
• LED indicators on Esc, F1 and F4 blink simultaneously:
66% to 100%
Do not press the power button to interrupt this progress.
Wait a few minutes until the logo screen is displayed.
An NVMe password is set. Type the password and press
Enter.