AOC 511Vwb, Service Manual

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15” LCD Color Monitor AOC 511Vwb
27
8.2 Trouble Shooting
8.2.1 MAIN BOARD
NO SCREEN APPEAR
Note:1. If replace “ MAIN-BOARD ” , Please re-do “DDC-content” programmed & “WHITE-Balance”.
Measured CN501 pin1
、
2
、
3 = 12 V?
Measured U501 pin 2= 5V?
Measured U503 pin 2= 3.3V?
NG
Check Correspondent component.
Is there any shortage or cold solder?
Yes .there have OSD show
Yes, all DC level exist
Disconnected the Signal cable( Loose the
Signal cable ),Is the screen show “Cable Not
Connected” ?
Connected the Signal cable again,
Check LED status.
Led Green
Replace U101
Flash Rom
No, nothing is
Connected the Signal cable
again
Check Power switch is in Power-on
status , and check if Power switch had
been stuck ?
Led Orange
OK, Keyboard no stuck
Led orange
Led Green
Check the Wire-Harness from CN401
Measured RGB (R405, R406, R407 )
H,V Input at U401 pin 8,9 ,was there
have signal ?
Check digital signal from CN201
Check Correspondent
component short/open
( Protection Diode )
NG
OK, Wire tight enough
Check Panel-Power Circuit Block
OK ,Panel Power OK
Check U401 Data-output Block
Re-do White balance adjust
OK, input Normal
NG, still no screen
OK, clock
OK
OK, U401 data OK
Replace Power board and Check
Inverter control relative circuit
Replace U401 ((RTD2025L)
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