MiTAC 7521 PLUS/N - Manual (Page 113)

112
7521 7521 Plus / N N/B MAINTENANCE Plus / N N/B MAINTENANCE
VGA CONTROLLER FAILURE
1. Confirm LCD panel or monitor is good
and check the cable are connected
properly.
2. Try another known good monitor or
LCD module.
Display
OK?
Remove all the I/O device & cable from
motherboard except LCD panel or extended
monitor.
Display
OK?
Replace faulty
LCD or monitor.
Connect the I/O device & cable
to the M/B one at a time to find
out which part is causing the
problem.
YES
NO
YES
NO
Replace motherboard
or into board-level
Troubleshooting.
Re-soldering.
NO
One of the following parts on the mother-board may be
defective, use an oscilloscope to check the following signal or
replace the parts one at a time and test after each replacement.
Parts:
U24 U2
J1 J2
Q2 Q3
Q4
Q15
Q14 U14
SW1 R5
R7 R150
L9
R18
R149 L537
L536 L534
Signals:
TXCLKOUT-
TXCLKOUT+
TXOUT0-
TXOUT0+
TXOUT1-
TXOUT1+
TXOUT2-
TXOUT2+
Check if
U24, U2, J1, J2
are cold
solder?
R[2~7]301
G[2~7]301
B[2~7]301
VBHSYNC
VBVSYNC
VBBLANK#
VGCLK
FPVCC
LID_OPEN# FA8 FA9
FA11 FA10
FA6 FA7
RP11 RP12
RP31 RP33
RP24 RP32
RP26 RP36
L540 R527
8.3 VGA CONTROLLER FAILURE LCD NO DISPLAY
There is no display or picture abnormal on LCD.
YES