No Power - Samsung LN26D450G1G Service Manual

4. Troubleshooting

4-1-2. No Power

The LEDs on the front panel do not work when connecting the power cord.
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Symptom The SMPS relay does not work when connecting the power cord.
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The units appears to be dead.
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The IP relay or the LEDs on the front panel does not work when connecting the power cord if the cables are
improperly connected or the Main Board or SMPS is not functioning. In this case, check the following:
Check the internal cable connection status inside the unit.
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Major
checkpoints Check the fuses of each part.
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Check the output voltage of SMPS.
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Replace the Main Board.
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Diagnostics
BD209 (B13 V), BD213 / 208(B5V)?
Does proper B3.3 V, B2.5 V, B1.06 V,
B1.5 V appear at L201 (B3.3 V)
appear at LVDS connector Pin #1 ~ 5
4-2
Power indicator LED on?
Yes
Does proper Stand-By DC
A5V appear at BD207?
Yes
Does proper Main
DC B13 V, B5 V appear at
Yes
Does proper DC A3.3 V
appear at IC202 (#5)?
Yes
BD1008 / 9 / 10 / 11 (B2.5 V)
BD1002 / 3 / 4 (B1.06 V)
BD1012 (B1.5 V)?
Yes
Does proper DC B13 V
of T-Con Board?
Yes
No
Change 18p power cable and SMPS.
No
No
Change the Main Assy.
No
No
No
Change the LVDS Cable.