No Power - Samsung LN32A650A1F Service Manual

4. Troubleshooting

4-1-1. No Power

The LEDs on the front panel do not work when connecting the power cord.
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The SMPS relay does not work when connecting the power cord.
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Symptom
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
Check the fuses of each part.
-
checkpoints
Check the output voltage of SMPS.
-
Replace the Main Board.
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Lamp(Backlight) Off, power indicator
Diagnostics
Does proper Inverter DC 120V appear
Does proper DC A3.3V appear at C128?
Does Proper VCC12, VCC33, VCC25
Caution Make sure to disconnect the power before working on the IP board.
4-2
LED on?
Yes
Does proper Stand-By DC
A5V appear at C114?
Yes
Does proper Main DC B13VS, B5V,
B13V appear at C110, C109, C111?
Yes
at CN101 in SMPS?
Yes
Yes
Does proper DC B3.3V, B8V, B9V_
CODEC, B1.2V appear at C101,
C129, C120, C139?
Yes
Does proper 1.2V_CORE,
appear at C1402?
Yes
appear at CD62, RD46, CD55
of FRC Board?
No
Check a connection power cable.
P/N: BN39-00802B
Change the Main Power assembly
32" : BN44-00208A
No
40" : BN44-00198A
46" : BN44-00203A
52" : BN44-00201A
No
No
Check IC102 Change the Main Ass'y
32" : BN94-1666D
40" : BN94-1666C
No
46" : BN94-1666B
52" : BN94-1666A
Check IC111, IC107, IC113, IC114
Change the Main Ass'y
32" : BN94-1666D
No
40" : BN94-1666C
46" : BN94-1666B
52" : BN94-1666A
Check IC110, IC112
Change the Main Ass'y
32" : BN94-1666D
No
40" : BN94-1666C
46" : BN94-1666B
52" : BN94-1666A
Check a other function (No picture part)
Replace a LCD Panel
No
32" : BN94-1666D
40" : BN07-00529A
46" : BN07-00530A
52" : BN07-00531A