Samsung SyncMaster BX2250, Service Manual

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4-7
4. Troubleshooting
4-4. When a blank screen is displayed (HDMI)
Symptom - Even though the LED power turns on, the screen is blank when connecting the HDMI cable.
Major checkpoints
- Even though the LED power turns on, the screen is blank when connecting the HDMI cable.
- Check the HDMI cable connections.
- Check whether the LVDS cable is connected correctly to the panel.
- Check whether the lamp connector of the panel is connected correctly to the Mainboard.
Diagnostics
Yes
Check the signal cables and
their connections.
Yes
Check and replace the circuits
related to 401.
No
①
Is X401 oscillating correctly?
②
Do the inputs appear at R171
to R176 and R241 to R246?
Check input part
No
Yes
Do output signals appear at pins 8 to 30
of CN400?
Check the circuits related to
CN400
No
Yes
Can DC 5V be measured at pins 1, 2,
and 3 of CN400?
Check the Panel EN signal
and the BL_EN signal.
No
Yes
Check and replace the panel.
Caution Make sure to disconnect the power before working on the Mainboard.