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4 Troubleshooting



4 Troubleshooting
4-1 First Checklist for Troubleshooting

1. Check the various cable connections first.
- Check to see if there is a burnt or damaged cable.
- Check to see if there is a disconnected cable connection or a connection is too loose.
- Check to see if the cables are connected according to the connection diagram.


2. Check the power input to the Main Board.


3. Check the voltage in and out between the SMPS Main Board, between the SMPS
INVERTER Board, and between the Main LVDS Boards.




4-1
4 Troubleshooting

4-2 Checkpoints by Error Mode

4-2-1 No Power

LAMP off, power indicator No
Check a connection a power cable.
LED blue color?


Yes



Does proper DC 12V No
Change a Assy PCB Power.
appear at CM801?



Yes


Does proper DC A3.3V, No Check a IC109, Q113.
A5V appear at
Change a main PCB ass'y.
C1034, C1032?


Yes


Does proper DC 5V, 3.3V, 2.5V No Check a IC100, IC114, IC106, IC107,
1.8V appear at C1024, C1102,
IC108. Change a main PCB ass'y
C1140?


Yes


No Check a other function.
A power is supplied to set? (No picture part)
Replace a lcd panel.




4-2
4 Troubleshooting

4-2-2 No Video (Analog PC)



Power Indicator is off.
Lamp on, no video.

Yes


Check a PC source and check No Input a analog PC signal and
the connection of DSUB cable? connected cable(DPMS).


Yes

Does the signal appear at No PC cable. Change a PC
1 #R5101, R2094, R5105
(R, G, B) of IC502? cable. Change a main PCB ass'y.


Yes


Check a LVDS cable? No
Replace a lcd panel? Please, Call to Samsung Co. LTD.




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4 Troubleshooting


WAVEFORMS

1




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4 Troubleshooting

4-2-3 No Video (Digital-HDMI)



Power Indicator is off.
Lamp on, no video.

Yes


Check the connection No
Input a HDMI cable.
of HDMI cable?


Yes

Does the digital data appear at
2 HDMI1 (R6100 ~ R6107)
HDMI2 (R6108 ~ R6115)?

Yes Check IC604.
No
Change a main PCB ass'y.

Does the digital data
appear at RA (618 ~ 623)?


Yes


Check a LVDS cable? No
Replace a lcd panel? Please, Call to Samsung Co. LTD.




4-5
4 Troubleshooting


2




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4 Troubleshooting

4-2-4 No Picture (Tuner_CVBS)



Power Indicator is off. No Connect the RF cable and
Lamp on, no picure. check RF signal.

Yes


Dose the signal appear No Check a B+ voltage (#7 of Tuner) 5V,
3
at R939? change a main PCB ass'y


Yes


Does the signal appear at No
4 Change a main PCB ass'y.
#M4 of IC502-1?


Yes


Check a LVDS cable? No
Replace a lcd panel? Please, Call to Samsung Co. LTD.




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WAVEFORMS

3 4




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4 Troubleshooting

4-2-5 No Picture (Video_CVBS)



Power Indicator is off. No
Check a A/V cable and video signal.
Lamp on, no picture.

Yes

Dose the signal appear at No
5 #P1 (R5127), P2 (R5200) Check a connection harness.
of IC502-1?

Yes


Check a LVDS cable? No
Replace a lcd panel? Please, Call to Samsung Co. LTD.




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4 Troubleshooting


WAVEFORMS

5




4-10
4 Troubleshooting

4-2-6 No Picture (S-VIDEO_Y,C)



Power Indicator is off. No Connect the s-video cable.
Lamp on, no picure. Operating a video player.
Yes
Dose the Y/C signal appear at No
6 #N2 (R5124), #T1 (R5111) Check a connection harness.
of IC502-1?

Yes


Check a LVDS cable? No
Replace a lcd panel? Please, Call to Samsung Co. LTD.




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WAVEFORMS
6




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4 Troubleshooting

4-2-7 No Sound

No
Picture is display, no sound. Connect a sound cable.
control a volume.


Yes


Does the signal appear at
Pin #10, #16(CH1_L, R Sound) No Check a connection harness and
6 and Pin #3, #9
headphone jack / Side AV.
(CH2_L, R Sound)
of IC111?


Yes


Check the DC 12V No Check a IC111.
of IC111? Change a main PCB ass'y.



Yes



7 Does the signal appear at No
L107, L108, L112, L113? Change a main PCB ass'y.



Yes



Replace the speaker ass'y?




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WAVEFORMS

7




4-14