Samsung PS42D5SX/XEC, Service Manual

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Troubleshooting
6-2 Samsung Electronics
6-2 Checkpoints by Error Mode
6-2-1 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 power of the unit seems to be out of order.
Major Checklist
The SMPS relay or the LEDs on the front panel do not work when connecting the power cord if the cables are improperly
connected or the Video Board or SMPS is out of order. 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 Video Board.
Troubleshooting
Procedures
Are the AC IN socket connector and
the Main SMPS CN800 connected?
The AC IN socket connector and
the Main SMPS CN800 connected
Is the Fuse (F101) of the Main SMPS
Power Input Part blown?
Replace Fuse (F101)
No
No
No
No
Yes
Yes
Yes
Main SMPS CN804-2
Pin 3: STB 5V
Pin 5 PS-ON: Check to see if it is 0V
Replace the Main SMPS
Replace the Main Board
Replace the Digital Board