AOC 919sz Service Manual

 
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7.3 Key Board 
715G2835  2 
 
 
                             
 

 
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8. Maintainability 
8.1 Equipments and Tools Requirement   
1. Voltmeter. 
2. Oscilloscope. 
3. Pattern Generator. 
4.  DDC Tool with an IBM Compatible Computer. 
5. Alignment Tool. 
6. LCD Color Analyzer. 
7. Service Manual. 
8. User Manual. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
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8.2 Trouble Shooting 
1. No Power 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
OK NG 
No power 
Check power cable is 
tightened? 
Check Power “On/Off” 
is “On”? 
Re-plug the power cable 
Replace main board and check connections 
Check the LED 
indicate is OK? Check the AC power   
Replace the power board and check connections 
OK NG 
OK NG 
NG
Turn on the Power “On/Off” switch 
Replace key board and check...

 
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2.  No Video (Power LED Green) 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
No Video (Power LED Green)
Press the power 
button is OK? 
Check the LVDS/FFC 
cable or panel 
The end  
NG
OK
OK
NG
Replace the main board 
Replace the power 
board and connection
Replace the LVDS/FFC 
cable or panel 
NG
The end  
Replace the key board 
NG
OK
Replace the main 
board and connection
OK
 

 
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3. DIM 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
OK 
The end 
OK 
The end 
OK 
The end 
DIM (image overlap, focus or flicker) 
Reset in factory mode 
Set to the optimal 
frequency, select the 
recommended fre
quency
Pull out signal cable and
check “Self Test Feature
Check” is ok? Check the signal cable 
and the PC 
Readjust the phase and pixel 
clock in the user mode 
Replace the main board
Replace the...

 
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4. Color is not optimal 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
NG
Color is not optimal
Miss color Color shift   
Replace the signal cable
Pull out the signal cable 
and check the screen 
color display is normal? 
The end
Replace the signal cable or PC
Reset the factory mode 
In the user mode, set the “color 
settings” until customer satisfy 
Replace the main board NG
OK
NG 
OK
NG 
 

 
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9. White- Balance, Luminance Adjustment 
Approximately 30 minutes should be allowed for warm up before proceeding white balance adjustment. 
How to setting MEM channel you can reference to chroma 7120 user guide or simpl use “SC” key and “NEXT” Key 
to modify xyY value and use “ID” key to modify the TEXT description Following is the procedure to do white-balance 
adjust . 
2. Setting the color temp. you want   
A. MEM.CHANNEL 3 Warm (6500K):...

 
39                                                           C. Adjust Cool (9300K) color-temperature 
1. Switch the Chroma-7120 to RGB-Mode (with press “MODE” button) 
2. Switch the MEM. Channel to Channel 9 (with up or down arrow on chroma 7120)   
3. The LCD-indicator on chroma 7120 will show x = 283 ±30, y = 297 ±30
 
4. Adjust the RED on factory window until chroma 7120 indicator reached the value R=100 
5. Adjust the GREEN on factory window until chroma 7120 indicator reached the value G=100 
6....

 
40                                                                  9. Monitor Exploded View For 919Pz