Display panel power rail built-in self-test (L-BIST)
About this task
Next steps
L-BIST
(LCD Power Rail Test) is an enhancement to the single LED error code diagnostics and is
automatically initiated
during
POST
.
L-BIST isolates if the LCD is receiving power from the system board. L-BIST checks if the system board is supplying power to the LCD by
performing an LCD Power Rail test. If there is no power going to the LCD, the battery status LED flashes a
[2,8] LED error code.
Display panel built-in self-test (LCD-BIST)
About this task
Steps
1. Press and hold the
D
key, and then press the
power
button.
2. Release both the
D
key and the
power
button when the computer begins POST.
3. The display panel begins to display a solid color, or cycling through different colors.
NOTE:
The sequence of colors may vary depending on the different display panel vendors. The user only must ensure
that the colors are being displayed correctly without distortion or graphical anomalies.
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Troubleshooting