Acer Extensa 4220 TravelMate 4320/4720 and Extensa 4220/4620 Service Guide - Page 114

Index of Symptom-to-FRU Error Message LCD-Related Symptoms Symptom / Error LCD backlight doesn't work LCD is too dark LCD brightness cannot be adjusted LCD contrast cannot be adjusted Unreadable LCD screen Missing pels in characters Abnormal screen Wrong color displayed LCD has extra horizontal or vertical lines displayed. Action in Sequence Enter BIOS Utility to execute "Load Setup Default Settings", then reboot system. Reconnect the LCD connectors. Keyboard (if contrast and brightness function key doesn't work). LCD inverter ID LCD cable LCD inverter LCD Mainboard Reconnect the LCD connector LCD inverter ID LCD cable LCD inverter LCD Mainboard LCD inverter ID LCD inverter LCD cable LCD Mainboard Indicator-Related Symptoms Symptom / Error Indicator incorrectly remains off or on, but system runs correctly Action in Sequence Reconnect the inverter board Inverter board Mainboard Power-Related Symptoms Symptom / Error Power shuts down during operation The system doesn't power-on. Action in Sequence Power source (battery pack and power adapter). See "Power System Check" on page 95. Battery pack Power adapter Hard disc drive & battery connection board Mainboard Power source (battery pack and power adapter). See "Power System Check" on page 95. Battery pack Power adapter Hard disc drive & battery connection board Mainboard 104 Chapter 4