ViewSonic Vx2255wmb-2 Service Manual

							
Packing For Shipping And Disassembly Procedure 
Packing For Shipping 
1. Packing Procedure 
1.1  Paste protection film to protect the monitor. (Figure 1) 
1.2  Put the monitor in the PE bag and  seal the bag with tape. (Figure 2) 
 
                                    
           Figure 1                                   Figure 2 
 
1.3  Put the cushions on the monitor.   
1.4  Place the monitor into the carton and  then put all the accessories into the 
carton. At last, close the car ton and seal it with tape. 
(Figure3)   
 
 
 
 
 
 
Figure 3 
 
 
 
 
 
AUDIO CABLE 
MONITOR HEAD 
DVI CABLE 
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Disassembly Procedure 
            
                                         
 HINGE  COVER 
                                          
            
                                            Adjust
 BASE 
 
           
                                           
BACK COVER 
 
           
 
 
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                                          Web camera  
 
         
                                            
BEZEL 
 
 
           
                                               
PANEL                                       
 
           
                                              
MICROPHONE   
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   Power key board 
 
 
            
 
 
            
                                              
 LVDS CABLE 
 
            
  
 KEYPOWER CABLE                                IF board 
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                                               I/F BOARD 
             
 
 
 
              
       
CHASSIS                                      SPEAKER 
 
 
  
            
         
 P/I  BOARD 
 
 
  
 
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6. Troubleshooting  Flow  Chart 
 
Common  Acknowledge 
z  If you change the interface board, be sure that the U103, U105, U106 and 
U108 these three components also changed to the new I/F board because 
there was program inside. If not, please  re-write EDID and upload firmware into 
U106 via VGA Cable. 
z   If you adjust clock and phase, please do it  at the condition of Windows shut down 
pattern. 
z   If you confirm the R.G.B. color is norma l or not, please do it under 16-grey scalar 
pattern.  
z   This LCM is analog interface. So if  the entire screen is an abnormal color that 
means the problem happen in the analog ci rcuit part, if only some scale 
appears abnormal color that stand the problem  happen in the digital circuit part.   
z   If you check the H/V position, please use the crosshatch pattern. 
z   This LCM support more than 30 timing modes , if the input timing mode is out of 
specification, the pict ure may appears abnormally. 
z   If brightness uneven, repairs Invert er circuit or change a new panel. 
z   If you find the vertical line or horizontal  line lost on the screen, please change panel. 
z   If you find the speaker don’t working,  please don’t plug in audio cable, unless 
change new speaker. 
 
Inverter/Power 
(Including 
AC/DC Power Interface Board
Keypad 
Flat panel (LV D S  i n t e r f a c e) and 
AC 
input Host computer 
Audio  
						

							
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6.1. 2 Interface BOARD DIAGRAM  
						

							
6.2 No Power & Power LED Off 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
No power
Check primary 
rectifier volta
ge 
Check IC802, 
C804,T801,
Check 
circuit if 
short
Check F801, P801, 
RT,801,D801 
Check pin6 of 
IC802 voltage 
about 12V 
CheckC810,D803,C80
7
,
Check pin2 of IC802 
v
oltage about 3V 
Check primary OVP, 
OLP and secondar
y 
Check pin1 of IC802 
voltage is below 1V Check R811, R810, 
R809
, R808,R814
END 
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Unstable power 
Check sampling 
  Circuit Check R822, 
R823, R824 
Change R822, 
R823, R824
Check the R pin 
voltage of IC803 
about 2 5V
Check R819, R820 
Check R818, D804, C807 if shor
t 
Change 
R818, D804, 
Check pin2 of 
IC802 voltage   
is3V
Check pin1 of 
IC802 voltage   
below1V
Change R808, R 809, R810, R 811, R815, 
END 
Check the C pin 
voltage of 
IC803 if 3V
Change 
IC803 
6.3  DC output voltage is unstable 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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6.4 Output power is unstable 
 
 
   
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Unstable power 
Check sampling 
  Circuit Check R822, 
R823, R824
Change R822, 
R823, R824 
Check the R pin 
voltage of IC803 
Check R819, R820 
Check R818, D804,  C807 if short
Change 
R818, 
D804,
Check pin2 
of IC802 
Check pin1 of 
IC802 voltage   
bl1V
Change R808, R 
809, R810, R 811, 
R815,
END 
Check the C 
pin voltage of 
IC803 if 3V 
Change 
IC803 
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