Samsung SyncMaster PX2370, Service Manual

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4-4
4. Troubleshooting
4-3. When the screen is blank (Analog)
Symptom
- Even though the LED power turns on, the screen is blank when connecting the DVI-I to D-sub
cable.
Major checkpoints
- Check the DVI-I to D-sub cable connections.
- Check whether the LVDS(FFC) cable is connected correctly to the panel.
- Check whether the lamp connector of the panel is connected correctly to the Inverter.
Diagnostics
CN400
CN600
CN601
CN101
IC300
X300
Yes
No
Check the R119, R122 and
R124 input terminals.
No
Check the circuits related to
IC200.
No Check the circuits related to
CN400.
Do output signals appear at pins 8 to 30
of CN400?
No Is DC 5V measured at pins 1, 2 and 3
of CN400?
Do the
3
Hsync and
4
Vsync
waveforms appear at pins 66, 67 of
IC300, respectively?
2
Do the RGB inputs appear at R119,
R122 and R124 of CN101?
1
Is X300 oscillating correctly?
Check and replace the panel.
No
Check and replace the circuits
related to X300.
Yes
Yes
Yes
Check the +5V_PANEL signal
and the BL_EN signal.
Yes
Check the signal cables and
their connections.
Yes
Caution Make sure to disconnect the power before working on the IP board.