Samsung SG626, SG628, BG626, BG678, SG676 Troubleshooting

7. Troubleshooting

Precautions

1. Is the power cord well connected to wall outlet?

2. Refer to the reference

1) No power

Start

Measure C03
(1000M/35V)

Measure IC02
OUT voltage

Measure IC03
OUT voltage

DC-Trans primary

power input?

Y

DC-Trans secondary

power input?

Y

Main PCB fuse

brown out?

N

Power input to IC02?

Y

DC 12V output

from IC02?

Y

DC 5V output

from IC03?

N

Are wires connected to

panel securely?

Y

Panel PCB Ass’y

is OK?

Y

OK

N

Check wires

N

Replace DC-Trans

N

Replace fuse

N

Check BD05 – 08

N

Check IC02(MC7812)

N

Check IC03(KA7805)

N

Check wire connection

Y

Reference 1

(Page. 38)

Replace panel PCB

28 Samsung Electronics

2) Compressor does not run

Precautions

1. Compressor does not operate in 5 minutes after power ON and compressor OFF.

2. Compressor does not run during defrosting.

3.

Compressor does not run because low temperature is detected if freezer sensor is not connected.

Start

Reference 6

(Page. 40)

N

Replace MICOM
and PCB

N

Replace IC07

N

Replace relay

5 minutes after

compressor off?

Y

Is compressor

operated by forse?

N

Reference 7

MICOM pin24

output is “HIGH ”?

Y

IC07 pin10 output

is “LOW ”?

Y

Comp relay is OK?

Y

N

Y

(Page. 41)

Check it after 5 minutes

Freezer sensor is

OK?

Y

Main PCB temperature

detector is OK?

Y

Check wiring

Reference 2

(Page. 38)

N

Replace sensor

N

Check detector &
replace PCB

Connector CON 8, 10

N

contects are OK?

Y

N

Check connector

Comp ass ’y is OK?

Y

Replace comp

Check wires connection

Samsung Electronics 29

3) No defrosting

Precautions

1. Even though both F·R-defrost sensors short-circuit, normal operation continues without
defrosting.(Refer to self-diagnosis function)

2. Even though the temperature fuse is off, there is no heating but defrosting natural
temperature increase comp off-time takes longer.

3. Even though both F·R-defrost sensor are open, heating does not end and comp-off
maintains with temperature fuse short-circuited.(Refer to self-diagnosis function)

Start

Y

A

R Defrost H #14
F Defrost H #15

R Defrost H #18
F Defrost H #19

R Defrost H RY01
F Defrost H RY09

Does defrosting

start if the forced defrost

key is pressed?

Y

Is power supplied to

defrost heater?

N

Are MICOM pin 14, 15

“HIGH”?

Y

Are IC 06 pin 17, 18

“LOW”?

Y

Defrost heater

relay is OK?

Reference 2

(Page. 38)

Connector CON C8, 09, 10

Evaparator temp. fuse

short-circuited?

Defrost P-cord short-

Y

are OK?

Y

Y

circuited?

N

N

Reference7
(Page. 41)
Measure resistance
of defrost sensor

N

N

N

N

N

N

Does the defrost-sensor

register –5˚C?

Y

Forced starting

Replace MICOM & PCB

Replace IC06

Replace relay

Replace CON

Replace temperature fuse

Replace EVAP ass’y

Check wire connection

30 Samsung Electronics