Samsung UN19C4000PD, Service Manual

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4-2
4. Troubleshooting
4-1-2. No Power
Symptom
The LEDs on the front panel do not work when connecting the power cord.
-
The SMPS relay does not work when connecting the power cord.
-
The units appears to be dead.
-
Major
checkpoints
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.
-
Check the fuses of each part.
-
Check the output voltage of SMPS.
-
Replace the Main Board.
-
Diagnostics
Does proper Stand-By DC A5V
appear at TP - A5V?
Does proper Main DC B13V, B5V
appear at TP - B13V, B5V?
Does proper DC A3.3V
appear at TP - A3.3V?
Does proper B3.3V, B1.8V,
SPI_3.3V appear at BD213 (B3.3V),
BD219 (DDR B1.8V) TP - SPI_3.3V ?
Does proper DC B13V
appear at LVDS connector
Pin #1~5 of T-con b'd?
A power is supplied to set?
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
Change the Main Assy.
26" : BN94-03399B
22"/19" : BN94-03399C
Change 18p power cable.
26"C4000 : BN39-01267A
22"C4000 : BN39-01267L
19"C5000 : TBD
Change the LVDS cable.
26"C4000 : BN96-12469L
22"C4000 : BN96-12447N
19"C5000 : TBD
Check a other function.
(No picture part)
Replace a LCD Panel.
26"C4000 : BN07-00847A
22"C4000 : BN07-00865A
19"C5000 : TBD
No
No
No
Lamp(Backlight) Off,
power indicator LED on?
Caution
Make sure to disconnect the power before working on the IP board.