Samsung 943NWX service manual When the screen is blank Analog

4. Troubleshooting

4-3. When the screen is blank (Analog)

Symptom	- LEven though the LED power turns on, the screen is blank when connecting the VGA cable.
	- Even though the LED power turns on, the screen is blank when connecting the VGA cable.
Major checkpoints	- Check the D-sub 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 IP board.
			CN 400
				IC 200
		X 201
					R111, R114, R118

		Check the signal cables and
		their connections.
			Yes
		① Is X201 oscillating correctly?		No	Check and replace the circuits
					related to X201.
			Yes
	② Do the RGB inputs appear at R111,			No	Check the R111, R114, and
		R114, and R118?			R118 input terminals.
			Yes
		Do the ③ Hsync and ④ Vsync		No	Check the circuits related to
Diagnostics	waveforms appear at pins 32, 33 of				IC200.
		IC200, respectively?
			Yes
	Do output signals appear at pins 8 to 30			No	Check the circuits related to
		of CN400?			CN400.
			Yes
				No
	Is DC 5V measured at pins 1, 2, and 3				Check the +5V_Panel signal
		of the CN400?			and the BL_EN signal.
			Yes
		Check and replace the panel.

Caution

Make sure to disconnect the power before working on the IP board.

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