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(1) Function to make service easy in case of occuring a trouble in the product.

(2) When occurring a trouble, if the button is pushed, but the function could not operate.

(3) If a toruble release during the representation of trouble, a refrigerator performs the normal function(RESET).

(4) To represent a ERROR CODE, it use FREEZE TEMP LEDs on TOP COVER. If ERROR occurs, the other LEDs except

ERROR CODE LEDs are all off.

1

FREEZER

FREEZER SENSOR open 

SENSOR abnormal

or short.

O

O

2

DEFROST

DEFROST SENSOR open 

SENSOR abnormal

or short.

O

O

No defrosting

3

DEFROSTING

DEFROST HEATER, 

FUNCTION

TEMP. FUSE open or

is abnormal

disconnection (Displayed 
after at least 4 hours 

O

O

O

from the trouble's
occurring.)

4

RT-SENSOR NOTE 

1)

Room Temperature

abnormal

SENSOR open or short 

O

O

O

- 19 -

F1

ERROR CODE LEDs

F2

F3

F4

15 minutes On/
15 minutes Off

* 

NOTE 1) If one second pass after pressing the QUICK FREEZE and FREEZE TEMP buttons togather in normal

operation, operates as follow.  

If normal, LEDs on the TOP COVER is all on. 
If abnormal, LEDs are all on except VACATION LED.

RT-SENSOR

:ON

O : OPERATE NORMAL

:OFF

(1) Function to check the testing function of PCB and refrigerator and to find where the trouble.

(2) The test switch is on the MAIN PCB of refrigerator.

TEST FUNCTION is released and RESET after MAX. 2hours regardless of TEST MODE.

(3) If the buttons on TOP COVER is pushed during TEST MODE, Function is not operated and only BUZZER ring with

"DING~ DONG~"

(4) After the end of TEST MODE, pull out the power cord and plug it in again(RESET).

(5) If a ERROR occurs during the TEST MODE, TEST FUNCTION is released and DISPLAY LEDs represent ERROR

CODE.

(6) If the TEST swithch is pushed during ERROR CODE, TEST FUNCTION is not operated.

TEST 1

Press TEST button 

1. COMP OPERATES SUCCESSIVELY.

once.

2. FAN OPERATES SUCCESSIVELY.
3. DEFROSTING HEATER OFF
4. ALL DISPLAY LEDS ON.

TEST 2

Press TEST button

1. COMP OFF.

If DEFROST HEATER 

once in the state of 

2. FAN OFF.

is over 7

°

C, it returns 

TEST MODE 1.

3. DEFROST HEATER ON.

to the NORMAL STATE.

4. ALL THE DISPLAY LEDS OFF EXCEPT 

QUICK FREEZE AND VACATION LEDS.

NORMAL

Press TEST button 

Return to the  initial condition. 

Comp starts 

STATE

once in the state of  

(RESET)

after 7 minutes.

TEST MODE 2.

- 20 -

• LED Check Function : Press the QUICK FREEZE and FREEZE TEMP buttons at the same time. After 1 sec., all the

LEDs of the DISPLAY are ON simultaneously. If release the BUTTON, return to the previous
condition.

TRANS secondary side is composed of electric power circuits for RELAY driving electricity (12Vdc) and for supplying
electricity to MICOM and IC (5Vdc). The voltage in each part is as follows.

VA1 is the part to protect over voltage and noise. When more than 385V is applied, the thermal-fuse(130

°

C cut-off, local

option) in a first part of TRANS is cut so that the elements in the secondary side of TRANS are protected.

CIRCUIT for occurring CLOCK which motivates the internal local element of IC1 to transmit and receive an information and
BASIC TIME for calculating time. Use a proper form for OSC 1. Because in case that SPECIFICATION is changed, the
calculated time in IC1 is changed or IC1 isn't able to operate.

All the internal parts of MICOM(IC1) return to the initial condition when the early power ON or apply power again in MICOM
after temporary power failure. As a result, all the functions operate acording to the early condition. At the early period of
power ON the "LOW" voltage is applied in the RESET terminal of MICOM for the fixed time. The RESET terminal is 5V
during the general operation.

- 21 -

PARTS

both ends of VA1

both ends of CM1

both ends of CM2

both ends of CE2

both ends of CC2

VOLTAGE

230Vac

14Vac

17Vdc

12Vdc

5Vdc

(1) LOAD OPERATION CHECK

ƒU

If the DOOR-R is opened during FAN MOTOR is operated, FAN MOTOR is stopped immediately.

ƒU

The  A  ,  B  of DOOR S/W-R is connected DOOR OPEN DETECTION CIRCUIT as follow.

ƒU

If the DOOR-R is opened or closed, then the DOOR S/W-R is ON/OFF, and the LAMP-R is ON/OFF,
and at the same time, S/W of the  A ,  B  of DOOR S/W-R for detection of DOOR-R open is ON/OFF.

(2) DOOR OPENING PERCEPTION CHECK

*NOTICE: If you would change DOOR S/W-R, must use the componenot of right PART NUMBER. Because there is a

similar type DOOR S/W-R of NOT MICOM MODEL, it's logic of the  A  ,  B  of DOOR S/W-R is reversed.

ƒU

Even though LAMP-R is operated a normal ON/OFF according to DOOR S/W-R, but the MICOM couldn't detect a 
DOOR-R opened or closed of lead wire of the  A  ,  B  is abnormal or S/W of the  A  ,  B  of DOOR S/W-R is abnormal.

ƒU

When DOOR-R open isn't detected : Even though DOOR-R is opened, FAN MOTOR couldn't stop.
When DOOR-R close isn't detected : Even though DOOR-R is closed, BUZZER sounds a DOOR OPEN ALARM.
check a lead wire of the  A  ,  B  and DOOR S/W-R.

- 22 -

KIND OF LOAD

COMP,

FAN MOTOR

DEFROSTING HEATER

COMP COOLING FAN

MEASURING POINT (IC5)

No.13

No.14 

No.15

ON

below 1V

STATE

OFF

12V

MEASURING POINT

NO.6 OF IC 1 (MICOM)

REFRIGERATOR DOOR

CLOSE

5V(S/W of  A  ,  B  is OFF state)

OPEN

0V(S/W of  A  ,  B  is ON state)