Filter
Top Products
Symptom/Error FRU/Action in Sequence
No beep, power-on
indicator off, LCD
blank during POST
Battery
AC Adapter
DC-DC & BATT board
System board
No beep, power-on
indicator on, LCD
blank during POST
Reseat DIMM.
CPU card
System board
No beep during
POST but system
runs correctly.
Speaker
LCD-Related Symptoms
Symptom/Error FRU/Action in Sequence
LCD backlight not
working
LCD too dark
LCD brightness
cannot be adjusted
LCD contrast cannot
be adjusted
1. Reseat the LCD connector.
2. Check the LCD inverter ID
3. LCD FPC
4. LCD inverter
5. LCD
6. System board
LCD screen unread-
able
Screen abnormal
Wrong color dis-
played
1. Reseat the LCD connector.
2. Check the LCD inverter ID
3. LCD FPC
4. LCD inverter
5. LCD
6. System board
LCD has extra hori-
zontal or vertical lines
displayed.
1. Check the LCD inverter ID
2. LCD FPC
3. LCD inverter
4. LCD
5. System board
Keyboard-Related Symptoms
Symptom/Error FRU/Action in Sequence
Keyboard (one or
more keys) doesn't
work.
1. Reseat the keyboard cable.
2. Keyboard
3. System board
Indicator-Related Symptoms
Symptom/Error FRU/Action in Sequence
Indicator incorrectly
remains off or on, but
system runs cor-
rectly.
1. Reseat the LED board.
2. LED board
3. System board
42 ThinkPad 390X / i 1700 HMM