Display Panel Power Rail Built-In Self-Test (L-Bist); Display Panel Built-In Self-Test (Lcd-Bist) - Dell Vostro 5501 Service Manual

Display panel power rail built-in self-test (L-BIST)

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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.
82 Troubleshooting