No-Beep Symptoms - Lenovo ThinkPad T490s Hardware Maintenance Manual

Error codes
0001: Reset error (platform reset not de-asserted)
0002: Internal bus error
0281: General embedded controller error
0282: Memory module error
0283: PCI resource error
0284: TCG-compliant functionality-related error (might be
the BIOS code validation failure)
0285: TCG-compliant functionality-related error (might be
the TPM initialization failure)
0286: Integrated graphics error
0287: Discrete graphics error
0288: Computer display error

No-beep symptoms

Table 4. No-beep symptoms
Symptom or error
No beep, power-on indicator on, LCD blank, and no
POST.
No beep, power-on indicator on, and LCD blank during
POST.
Solutions
1. Remove the ac power adapter and the removable
battery if your computer has one. Then, reset the
computer by doing one of the following:
• For models with the emergency-reset hole,
insert a straightened paper clip into the
emergency-reset hole. Wait for one minute.
Then, reconnect all power resources and restart
the computer.
• For models without the emergency-reset hole,
press and hold the power button for about
seven seconds. Then, reconnect to all power
resources and restart the computer.
2. Replace the system board (service provider only).
Replace the system board (service provider only).
Replace the system board (service provider only).
1. Reinstall or replace the memory module.
2. Replace the system board (service provider only).
1. Remove PCIe devices (the M.2 card, PCIe card,
and so on) (service provider only).
2. Replace the system board (service provider only).
Replace the system board (service provider only).
Replace the system board (service provider only).
Replace the system board (service provider only).
1. Reinstall or replace the discrete graphics card
(service provider only).
2. Replace the system board (service provider only).
1. Reconnect the display cable on both the system
board side and the computer display side (service
provider only).
2. Replace the system board (service provider only).
FRU or action, in sequence
1. Run LCD Self Test.
2. Ensure that every connector is connected tightly and
correctly.
3. Reseat memory module.
4. Replace the system board.
1. Run LCD Self Test.
2. Reseat memory module.
3. Replace the system board.
Chapter 4
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Related service information
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