Samsung EX2220 Service Manual page 28

4-4. When a blank screen is displayed (Digital)
Symptom - Even though the LED power turns on, the screen is blank when connecting the DVI cable.
- Even though the LED power turns on, the screen is blank when connecting the DVI cable.
- Check the DVI cable connections.
Major checkpoints
- Check whether the LVDS cable is connected correctly to the panel.
- Check whether the lamp connector of the panel is connected correctly to the IP board.
Diagnostics
Caution Make sure to disconnect the power before working on the IP board.
R109, R110, R113
Check the signal cables and
their connections.
Yes
① Is X401 oscillating correctly?
Yes
② Do the inputs appear at R206,
R210, and R213?
Yes
Do output signals appear at pins 8 to 30
of CN400?
Yes
Can DC 5V be measured at pins 1, 2,
and 3 of CN400?
Yes
Check and replace the panel.
CN400
X401
IC400
No
No
No
No
4. Troubleshooting
Check and replace the circuits
related to X401.
Check the R206, R210, and
R213 input terminals.
Check the circuits related to
CN400.
Check the Panel EN signal
and the BL_EN signal.
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