74 Chapter 4Index of Symptom-to-FRU Error MessageLCD-Related SymptomsSymptom / Error Action in SequenceLCD backlight doesn't work First, plug a monitor to CRT port. Next, enter BIOS utility to running“Load Default Settings” then reboot the system.Reconnect the LCD connectors.Keyboard (if the brightness function key doesn't work).LCD cableLCD inverterLCDMain boardLCD is too darkLCD brightness cannot be adjustedEnter BIOS Utility to execute “Load Setup Default Settings”, thenreboot system.Reconnect the LCD connectors.Keyboard (if the brightness function key doesn't work).LCD cableLCD inverterLCDMain boardUnreadable LCD screenMissing pels in charactersAbnormal screenWrong color displayedLCD has extra horizontal or vertical linesdisplayed.Reconnect the LCD cableLCD cableLCDMain boardIndicator-Related SymptomsSymptom / Error Action in SequenceIndicator incorrectly remains off or on, but systemruns correctlyMain boardHDD/CD-ROM active indicators cannot work HDD/CD-ROM driveDevice driverMain boardPower-Related SymptomsSymptom / Error Action in SequencePower shuts down during operation Power source (battery pack and power adapter). See “PowerSystem Check” on page 65.Battery packAC adapterSee if the thermal module is overheat (Heat sink or fan).Main boardThe system cannot power-on. Power source (battery pack and power adapter). See “PowerSystem Check” on page 65.Battery packPower adapterCPUMain boardThe system cannot power-off. In Windows XP operating system, hold and press the power switchfor more than 4 seconds. If the system can power off, then the mainboard is OK. Verify OS in the HDD.Main board