Table 20. Functions (continued)
M-BIST
L-BIST
Trigger
Press the <M> key and the power
button.
Integrated into the single LED error
code diagnostics. Automatically initiated
during POST.
Indicator of fault
Battery LED light with
Solid Amber
Battery LED error code of [2,8] blinks
Amber x2, then pause, then blinks White
x8.
Repair instruction
Indicates a problem with the system
board.
Indicates a problem with the system
board.
System board built-in self-test (M-BIST)
About this task
Steps
1. Press and hold both the M key and the power button to initiate M-BIST.
2. The battery-status light illuminates in amber when there is a failure with the system board.
3. Replace the system board to fix the issue.
NOTE:
The battery status LED will not illuminate if there is no failure present with the system board. If further
troubleshooting is required, proceed with the applicable Guided Resolution for No Power/No POST, etc.
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.
84
Troubleshooting
