MiTAC MiNote 7321, Service Manual

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7321 N/B Maintenance 7321 N/B Maintenance
Check
J3,J5 for cold
solder
?
One of the following parts or signals on the motherboard may be
Defective, use an oscilloscope to check the signals or replace the
Parts one at a time and test after each replacement.
Yes
No
Re Re - - soldering soldering
Parts : : Signals:
ENABLE_VGA BLADJ
PANEL_VDD ENABLE_BL
FPVCC EN_BL
TXOUT[12:10]-
TXOUT[12:10]+
TXOUT[22:20]- TXOUT[22:20]+
TXOUTCKL1,2- TXOUTCLK1,2+
LCD NO DISPLAY
Replace following
parts and test after
each replacement
1. LCD
2. LCD cable
3. Inverter BD
Board-level
Troubleshooting
Replace
Motherboard
Try another known good LCD
module.
Display
Ok?
Yes
No
Display
Ok?
No
Yes
1. Turn on power.
2. Try to adjust the LCD backlight by the
keyboard hot-key to avoid the case of LCD no
display caused by the backlight to be adjusted
to too dark.
End
Q502 Q511
Q501 L507
D5 U30
L24 R635
R513 R53
R56 C231
C14 C23
R57 SW2
8.4 LCD No Display Or Picture Abnormal
Symptom:
The LCD shows nothing or abnormal picture, but it is ok for external monitor.