No Video (Tuner Dtv) - Samsung UN HU7250F Series Service Manual

4-2-4. No Video (Tuner DTV)

Symptom Audio is normal but no picture is displayed on the screen.
• Check the DTV source.
Major • Check the Tuner.
checkpoints
• This may happen when the LVDS cable connecting the Main Board and the Panel is
disconnected.
Diagnostics
1
2
Make sure to disconnect the power before working on the IP Board.
Caution
Power indicator LED is off.
Lamp(Backlight) on, no video.
Yes
Check the RF source and check the
connection of RF cable.
Yes
Check the 'signal strength' in Self
Diagnosis menu Strength is enough.
Yes
Check the Power of Tuner.
Pin #4 of Tuner : B1.8V_Tuner
-
Pin #1 of Tuner : B3.3V_Tuner
-
Yes
Check the LVDS clk signal at output of
Main Board. (TX)
TX6_CLK : TCON SDA
-
TX8_DATA : TCON SCL
-
Yes
Check the LVDS cable?
Replace the T CON / LCD panel?
No Check a set in the 'Stand-by mode'.
No Input the RF source properly.
No Check the DTV source.
No Change the Main Ass'y.
Check IC1400(NT14U).
No
Change the Main Ass'y.
Yes Please, Contact tech support.
4. Troubleshooting
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