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6. TROUBLE SHOOTING FLOW CHART

(VE710s-2/VE710b-2/VA721)

6.1.

NO POWER
POWER STAR Check 3.3V O/P C825 12V Check P802 5,6 PIN Check P901,P902

PANEL

Check 12V O/P C823

Check I901 L901,L903 T901,T902 Q904,Q905

Check F801 D801~D804

Check D822 I802,I803

3.3V

Check I901

Check I801 ,Q801

12V

MAIN PCB

STAR

CHECK MAIN PCB

5V OK?

N

CHECK POWER PCB OK?

Y N 3.3V OK? CHECK I103, SUROUND CAP BEAD OK? CHECK I106,I107 SUROUND CAP OK?

Y N 1.8V OK? CHECK I104, SUROUND CAP BEAD OK? CHECK I101, SUROUND CAP BEAD OK?

6.2.

NO DISPLAY
No Display

Check Power region

Dark

Check LED Color

Amber

Check IO cable is connect OK ?

Yes

Check I/P signal is in pwr saving state? No Check I106 is OK ?

Amber & Green Green Check X102 Crystal 12MHz is working? Yes Refer to NO POWER trouble shoot flow char Press Power key ON/OFF is OK ? (See LED is green or dark.) No Check uP I106 Reset is Ok ? Yes

Change I106

Yes No

No

Check Reset circuit C173,D125

Press "1" key if OSD menu is on display ?

Check Keypad pcb is OK ? Yes Check if Inverter is Ok ? No Change Inverter

Yes Check I105 MST8016A if HWRST Pin#32 have reset pulse ? Yes Check X101 Crystal 14.318MHz is working ? Yes Check I105 Pin#70,71 data bus have signal Yes Check panel Powers VLCD_3V3 VLCD_12V correct Yes Change LCD panel No No

No

Check uP I106 pin#17 send reset pulse ? Yes

Change X101

Change I105 LCD controller IC