Samsung HPR4272X/XAC, 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?
Is the Fuse (F101) of the Main SMPS
Power Input Part blown?
Check Main SMPS CN804-2
Pin 3: STB 5V = 5V
Pin 5 PS-ON = 0V
Replace the Main Board
Connect The AC IN socket connector
and the Main SMPS CN800
Replace the Main SMPS
Replace the Main SMPS