6-10
5. Switching power circuit failure
NO
YES
Is +12V power source available?
(IC18 pin7, 8)
Failure point
1) Check IC20 Pi 7 approxi5.1V. (ZD04)
2) Check IC21 and IC22 if broken.
3) Check D19, L33, IC12, IC20 if any one break.
Is +5Vx ok? (This is all TTL IC
power source)
Make sure that the voltage of
between IC22 pins 7, 8 and GND
approximately 5V.
NO
YES
Failure point
1) Check Adapter.
2) Check F1 (fuse).
3) Check JP01.
NO
Is IC22 Pin 1 +5V?
1) Make sure that the voltage of between IC18 pin1
and GND appro5V.
2) Make sure that the voltage of between IC22 pin5
and GND appro5V
3) Make sure that the voltage of between IC22 pin7
and GND appro5V.
4) Make sure that the voltage of between IC18 pin5
and GND appro5V.
Failure point
1) Check IC25 Pin 3 (CPU) if Low-level.
2) Check IC18 ok?
NO
YES
Check power of IC18 Pin 5 and
Pin 6 is 5V. (This is ADC, Scalar,
LVDS power source)
YES
Is VLCD approximately 5V?(This
is panel power source)
1Make sure that the voltage of
between IC22 pin 5 and pin6 to
GND approximate 5V.
Failure point
1) Check IC20 Pin 5 appro5V.
2) Check IC19 and IC22 if broken.
3) Check D20, L34, IC12, IC20 if any one is broken?
NO
Is IC22 Pin 3 about +5V?
YES
Failed
Next page
Failure point
Check over voltage protection circuit
work? (IC20 pin14 High level)
Failure point
Check over voltage protection circuit
work? (IC20 Pin13 High level)
Summary of Contents for LCD1920NX BK - MultiSync - 19" LCD Monitor
Page 4: ...1 1 USER S MANUAL 1 A Version MultiSync LCD1920NX TM ...
Page 49: ...3 6 SYMBOL CODE DESCRIPTION 15 79PZ0004 LCD MODULE 19 0 TFT FLC4 15 ...
Page 100: ...7 9 2 4 3 Circuit diagram ...
Page 172: ...MODEL LCD1920NX LCD MAIN BD 1 7 SCHEMATIC DIAGRAM 10 1 Schematic Diagram ...
Page 173: ...MODEL LCD1920NX LCD MAIN BD 2 7 SCHEMATIC DIAGRAM 10 2 ...
Page 174: ...MODEL LCD1920NX LCD MAIN BD 3 7 SCHEMATIC DIAGRAM 10 3 ...
Page 175: ...MODEL LCD1920NX LCD MAIN BD 4 7 SCHEMATIC DIAGRAM 10 4 ...
Page 176: ...MODEL LCD1920NX LCD MAIN BD 5 7 SCHEMATIC DIAGRAM 10 5 ...
Page 177: ...MODEL LCD1920NX LCD MAIN BD 6 7 SCHEMATIC DIAGRAM 10 6 ...
Page 178: ...MODEL LCD1920NX LCD MAIN BD 7 7 SCHEMATIC DIAGRAM 10 7 ...