Samsung PPM63M7FS Service Manual page 24

■ When the unit is repeatedly turning on and off
Symptom - The SMPS relay is repeatedly turning on and off.
In general, the SMPS relay repeatedly turns on and off by the protection function due to a defect on a board
connected to the SMPS.
- Disconnect all cables from the SMPS, operate the SMPS alone and check if the SMPS works properly and if
Major
each voltage output is correct.
Checklist
- If the symptom continues even when SMPS is operated alone, replace the SMPS.
- If the symptom is not observed when operating the SMPS alone, find any defective assemblies by
connecting the cables one by one.
②
①
Troubleshooting
Procedures
WheN SeParaTINg aND CONNeCTINg The CaBleS SuCh aS CN807, CN808, CN809, CN810, CN811 Of The
MaIN SMPS, CN4000 Of The X MaIN BOarD, aND CN5004 Of The Y MaIN BOarD, a SPark MaY Be geNeraTeD
Caution
BY The eleCTrIC Charge Of The hIgh CaPaCITY CaPaCITOr. TherefOre, WaIT SOMe TIMe afTer
DISCoNNECTINg ThE PowER CoRD FRoM ThE uNIT.
Samsung Electronics
①
Does the symptom continue when
connecting the power after removing CN810
from the SMPS?
Yes
②
Does the symptom continue when
connecting the power after removing CN809
from the SMPS?
Yes
③
Does the symptom continue when
connecting the power after removing CN807
from the SMPS?
Yes
Replace the Main SMPS
No
Replace the
Y Main Board
No
Replace the
X Main Board
No
Replace the
Logic Board
Troubleshooting
③
4-3