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6.2. NO DISPLAY
No
Display
Check LED Color
Check Power
region
Refer to NO POWER
trouble shoot flow char
t
Check IO cable is
connect OK ?
Amber
Dark
Check I/P signal is in
pwr saving state?
Yes
Check X100 Crystal
12MHz is working?
Amber & Green
Check I002 is OK ?
Press Power key
ON/OFF is OK ?
(See LED is green or
dark.)
Check uP I105
Reset is Ok ?
No
Change
I105
Yes
Check Reset circuit
Q113,D113
No
Yes
Press "1" key if OSD
menu is on display ?
Yes
Check Keypad
pcb is OK ?
No
Check if
Inverter is Ok ?
Yes
Change
Inverter
No
Check I001 MVZ if
RST Pin#155 have
reset pulse ?
Check uP I105
pin#24 send reset ?
pulse ?
No
Yes
Check X101 Crystal
12MHz is working ?
Change X101
No
Yes
Yes
Check J105,J106
data bus have signal
Change I001 LCD
controller IC
No
Yes
Check panel Powers
VDDD=3.3V
VDDA=9.2V
VDDG=18V
VEEG=-6V
Yes
Change LCD panel
Yes
No
Green
!
!
ViewSonic Corporation
16
Confidential
– Do Not Copy
VE155s
, VE500-2
VE
15
5
/b, VA520-2