Samsung RF26XAEPN Troubleshooting, Start, ReplacePCBASSY, Solder again 2 Replace PCB MAIN

TROUBLESHOOTING

4-2-6. If Power is not supplied

Caution

At the power of main PCB, the AC115V power and a high-voltage over DC 170V are occurred.Please take care of yourself during repair and measurement.

Check in SMPS PBA

Checking method of voltage

CN70 input ; CN70#9(Red) #11(Gray)

AC voltage

Checking method of DC 2nd output voltage

REG1 input ; Regulator 7805 same as C107

terminals.
DC 13.0V	0.8V

Start

Is the plug connected in?

Is power 115V applied to the both terminals of SMPS PCB CN70 #11-#9?

Is fuse on the SMPS

PCB down?

Is DC170V

applied to the both terminals of BD1+,-

Is DC5.8V

applied between TOP switch 246Y C and S?

-Refer to the function and reference parts in the manual when check the MAIN PCB

Connect plug again, check the plug loosening

Check the assembly and wire connection

1)ReplaceFUSEAC250V2.0A

2)ReplacePCBASS’Y

1)CheckPCBPATTERNandreplaceBD1

2)ReplacePCBASS'Y

ReplacePCBASS'Y

Checking method of DC 2nd output voltage REG1 output ; Regulator 7805 same as C109 terminals.

DC 5V 0.5V

-Check MAIN PCB connection

-Check the connections between cabinet and door

-Check the connections between door and panel PCB

Is 13V applied to the both

terminals of C107?

Is 5V applied to the both

terminals of C109?

Does Panel PCB operate normally?

Is the load (i.e. Relay)

normal?

Is there any PCB soldering, short, breakage?

Normal(Recheck)

Replace PCB ASS'Y

1)Check REG1 (KA7805)

2)Replace PCB ASS'Y

1)Checkassemblywireandrepair

2)ReplacePanelPCB

1)Check the contact of lead wire

2)Replace the applicable relay / PCB MAIN

1)Solder again

2)Replace PCB MAIN

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