No Power - Samsung LN32A550P3F 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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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.
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Replace the Main Board.
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Lamp(Backlight) Off, power indicator
Does proper Main DC B13V,B12V,B5V
Diagnostics
Does proper Inverter DC 120V appear
Does proper DC D3.3V,B8V,CORE1.1V
Make sure to disconnect the power before working on the IP board.
Caution
4-2
LED on?
Yes
Does proper Stand-By DC STB5V
appear at BD100?
Yes
appear at BD105L,C1261,BD101?
Yes
at CN801 in IP?
Yes
Does proper DC STB3.3V
appear at C101?
Yes
appear at C108,C110,C137?
Yes
Does proper D1.8V,A2.5V,A1.2V
appear at C115, C111, C112?
Yes
A power is supplied to set?
No
Check power cable.
P/N: BN39-00702F
Change the Main Power assembly
No
BN44-00202A
No
No
Check IC105 Change the Main assembly
No
BN94-01628C
Check IC101,IC108,IC102
No
Change the Main assembly
BN94-02077B
Check IC104, IC106, IC107
No
Change the Main assembly
BN94-02077B
Check a other function (No picture part)
No
Replace a LCD Panel
BN07-00518A