Display Panel Built-In Self-Test (Lcd-Bist); Outcome - Dell Vostro 5502 Service Manual

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)

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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.
4. The computer reboots at the end of the last solid color.

Outcome

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The following table shows the outcome of running different types of BIST.
Table 20. BIST outcome
Off
Solid amber
88 Troubleshooting
M-BIST
No fault detected with system board.
Indicates a problem with the system board.