Samsung SyncMaster 570B TFT Service Manual page 13

4 Troubleshooting
4-2 No Video (CN15MSS/MOS)
Power indicator is green
Does the clock pulse
appear at Pin 84 of
IC133?
Yes
1 2
Do the sync pulses appear at
Pins 30 and 31 of IC251?
Yes
7
Do the waveforms appeaer at
Pins 1 and 16 of CN251?
Yes
Replace LCD Panel
WAVEFORMS
1 IC251 #30
CH1 RMS= 2.8V
IC182 #9
5
CH1 RMS =3.1V
4-2
No
Does the H-sync pulse appear
No
Do the sync pulses appear at
Replace IC251 or check
No
Replace IC251 or check
2 IC251 #31
CH1 RMS= 2.12V
IC203 #1
6
CH1 RMS =4.56V
3
at Pin 94 of IC133?
Yes
Replace IC133.
6
Pins 70 of IC203?
Yes
its related circuit.
its related circuit.
3 IC133 #31
CH1 RMS= 2.12V
IC251 #141
7
CH1 RMS =2.3V
4
No
Does the pulse appear at Pin 9
of IC182 or Pin 1 of IC181?
Replace IC182.
Replace IC181(SOG)
or check R181 and PIN 13 of
CN102
No
Replace IC203 or check its
related circuit.
4 IC182 #94
CH1 RMS = 3.5V
SyncMaster 570B TFT / 580B TFT
5
No
Yes