Samsung UN32D5500RF, Service Manual

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4-2
4. Troubleshooting
4-1-2. How to check fault symptom
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
Main Assy
1 B5V 2 SW_PW
3 B5V 4 A5V
5 GND 6 GND
7 B12VS 8 GND
9 B12VS 10 SW_INV
11 B13V 12 NC
13 B13V 14 DMM
Power Assy
1 B5V 2 SW_PW
3 B5V 4 A5V
5 GND 6 GND
7 B12VS 8 GND
9 B12VS 10 SW_INV
11 B13V 12 NC
13 B13V 14 DMM
Main Ass’y
14p cable
Speaker
Power Ass’y
LVDS cable
T-con
-
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Check an AC power connection. Power indicator LED on?
Change 14p power cable and SMPS.
Check the backlight on,
when 14p cable unconnected ?
Change 14p power cable and SMPS.
Check ‘Stand-By 5V’ DCA5V
appear at BD207?
Change 14p power cable and SMPS.
Check Power input of Main Ass’y ?
DC B13V, B5V appear at BD209(B13V),
BD213/208(B5V)?
Change the Main Assy.
Check Power input of submicom IC(A3.3V) ?
Check Power of nand flash IC(B3.3V)
Check Power of main IC(B2.5V, B1.1V)
Check Power of DDR IC(B1.5V) appear at
IC202(#5) L201 (B3.3V) BD1008/9/10/11
(B2.5V) BD1002/3/4 (B1.1V) BD1012 (B1.5V)
Change the LVDS cable.
Check Power of LVDS (13V) appear at
LVDS connector Pin #1~5 of T-con b’d?
Change the T-con b’d.
Does proper DC B13V
appear at F1 of T-con b’d?
Please, Contact tech support.
No
No
No
No
No
No
No
Caution Make sure to disconnect the power before working on the IP board.