LG LSC27926 Service Manual

REFRIGERATOR

SERVICEMANUAL

CAUTION

PLEASE READCAREFULLY THE SAFETY PRECAUTIONS OF THIS MANUAL BEFORECHECKING OR OPERATING THE REFRIGERATOR.

MODEL : LSC27926**

CONTENTS

WARNINGS AND PRECAUTIONS FOR SAFETY ................................................................................................................ 3

SPECIFICATIONS................................................................................................................................................................... 4

PARTS IDENTIFICATION....................................................................................................................................................... 5

HOW TO INSTALL THE REFRIGERATOR .......................................................................................................................... 6

HOW TO ADJUST DOOR HEIGHT.................................................................................................................................... 6

FILTER................................................................................................................................................................................ 7

HOW TO CONTROL THE ICEMAKER WATER SUPPLY.................................................................................................. 8

MICOM FUNCTION .............................................................................................................................................................. 10

EXPLANATION OF MICOM CIRCUIT.................................................................................................................................. 23

EXPLANATION OF PWB CIRCUIT.....................................................................................................................................23

PWB PARTS DIAGRAM AND LIST.....................................................................................................................................40

PWB CIRCUIT DIAGRAM...................................................................................................................................................43

ICE MAKER AND DISPENSER WORKING PRINCIPLES AND REPAIR ...........................................................................46

WORKING PRINCIPLES.................................................................................................................................................... 46

FUNCTION OF ICE MAKER .............................................................................................................................................. 47

ICE MAKER TROUBLESHOOTING................................................................................................................................... 48

ICE MAKER CIRCUIT .........................................................................................................................................................49

CIRCUIT................................................................................................................................................................................ 53

TROUBLE DIAGNOSIS........................................................................................................................................................ 54

TROUBLESHOOTING ....................................................................................................................................................... 54

FAULTS .............................................................................................................................................................................. 64

COOLING CYCLE HEAVY REPAIR ................................................................................................................................. 81

HOW TO DEAL WITH CLAIMS ........................................................................................................................................ 88

HOW TO DISASSEMBLE AND ASSEMBLE..................................................................................................................... 93

DOOR............................................................................................................................................................................... 93

HANDLE........................................................................................................................................................................... 94

FAN SHROUD GRILLE .................................................................................................................................................... 95

ICEMAKER ASSEMBLY................................................................................................................................................... 95

DISPENSER..................................................................................................................................................................... 96

EXPLODED VIEW &

REPLACEMENT PARTS LIST ........................................................................................................................................... 98

- 2 -

WARNINGS AND PRECAUTIONS FOR SAFETY

Please observe the following safety precautions to use the refrigerator safely and correctly and to prevent accident or injury when servicing.

1. Be careful of an electric shock. Disconnect power cord from wall outlet and wait for more than three minutes before replacing PWB parts. Shut o the power whenever replacing and repairing electric components.

2. When connecting power cord, please wait for more than ve minutes after power cord was disconnected from the wall outlet.

3. Please check if the power plug is pressed by the refrigerator against the wall. If the power plug was damaged, it could cause re or electric shock.

4. If the wall outlet is overloaded, it may cause a re. Please use a dedicated circuit for the refrigerator.

5. Please make sure the outlet is properly grounded. Particularly in a wet or damp area.

6. Use standard electrical components.

7. Make sure hooks are correctly engaged. Remove dust and foreign materials from the housing and connecting parts.

8. Do not fray, damage, run over, kink, bend, pull out, or twist the power cord.

9. Please check for evidence of moisture intrusion in the electrical components. Replace the parts or mask with insulation tape if moisture intrusion was conrmed.

10. Do not touch the icemaker with hands or tools to conrm the operation of geared motor.

11. Do not suggest that customers repair their refrigerator

themselves. This work requires special tools and knowledge. Non-professionals could cause re, injury, or damage to the product.

12. Do not store ammable materials such as ether, benzene, alcohol, chemicals, gas, or medicine in the refrigerator.

13. Do not put anything on top of the refrigerator, especially something containing water, like a vase.

14. Do not put glass bottles with full of water into the freezer. The contents will freeze and break the glass bottles.

15. When you scrap or discard the refrigerator, remove the doors and dispose of it where children are not likely to play in or around it.

- 3 -

SPECIFICATIONS

ITEMS SPECIFICATIONS

DIMENSIONS 912X829X1771 mm

WXD

(35.9x32.6x69.7in)

286.6

).sbl(gk301THGIEWTEN

COOLING SYSTE Fan Cooling

TEMPERATURE CONTROL

DEFROSTING SYSTEM

Micom Control

Full Automatic

Heater Defrost

enatneP-olcyCNOITALUSNI

COMPRESSOR

EVAPORATOR

CONDENSER

REFRIGERANT

LUBRICATING OIL

PTC Starting Type

Fin Tube Type

Wire Condenser

R134a(185g)(6.5oz)

FREOL @ 10G(310cc)

ITEMS SPECIFICATIONS

CAPILLA R Y TUBE ID Ø0.8 5

FIRST DEFROST

DEFROST CYCLE

DEFROSTING DEVICE

ANTI-SWEAT HEATER

4-5 Hours

13-15 Hours

Heater, Sheath

Dispenser Duct Door Heater

Dispenser Heater

ANTI-FREEZING HEATER

Water Tank Heater

Damper Heater

FREEZER LAMP

REFRIGERATOR LAMP

DISPENSER LAMP

40W (1 EA)

40W (4 EA)

15W (1 EA)

7-HXEVEISRALUCELOMREIRD

in.)

1 1

1771 mm (69

in.)

1741.5 mm (68

in.)

1 1

1771 mm (69

1746.5 mm (68

1004 mm (391/2 in.)

912 mm (35.9in.)

weiVpoTweiVtnorF

in.)

829 mm (32

724 mm (28

779 mm (30

in.)

897 mm (35

1261 mm (49

- 4 -

PARTS IDENTIFICATION

Frame Display

Dispenser Lamp

Ice & Water

Dispenser Button

PWB Cover

Water Tubes

Freezer

Compartment

Refrigerator

Compartment

Humidity Switch

Lamp

Shelf

Snack Drawer

Vegetable Drawer

Vegetable Drawer /Meat Drawer

Door Rack

Shelf

Door Rack

Wine Holder

Lamp

Lower Cover

Dairy Product Corner

Door Rack

Drawer

(Wire/Plastic)

Automatic

Icemaker

Door Rack

Shelf

Bottle Guide

Door Rack

Water Filter

Egg Box

- 5 -

HOW TO INSTALL REFRIGERATOR

1. How to Adjust Door Height of Refrigerator

Make the refrigerator level first. (If the refrigerator is not installed on a flat floor, the height of freezer and refrigerator door may not be the same.)

1. If the freezer door is lower than the refrigerator door:

2. If the freezer door is higher than the refrigerator door:

1 2

- 6

HOW TO INSTALL REFRIGERATOR

2. Filter

Replace the filter when the indicator light comes on or the performance of the icemker or water dispenser decreases noticeably.

After changing the water filter cartridge, reset the water filter status display and indicator light by pressing and holding the BUTTON for 3 seconds.(page 18)

1. Remove the old cartridge.

Twist the knob of the cartridge counter clockwise.

2. Replace with a new cartridge.

Take the new cartridge out of its packaging and remove protective cover from the o-rings.

With cartridge knob in the vertical position, push the new filter cartridge into the cover until it stops.

If you can’t turn the filter from side to side, it isn’t fully inserted. Push it in firmly and twist it into place. You will hear the snap when it clicks into place.

Using the handle, twist the cartridge clockwise about 1/4 turn.

When the cartridge is removed, you will feel it click .

Pull out the cartridge.

NOTE: There will be some water(25cc) in the filter

cartridge. Some spilling may occur. Catch it in a bowl or towel.

3. Flush the Water System After Replacing Filter Dispense

water through the water dispenser for 3 minutes to purge the system. There may be a little air in the line, causing noise or hissing. Run the water at the dispenser until the hissing stops to purge the air from the system.

NOTE: - To purchase replacement water filter cartridges,

visit your local appliance dealer or part distributor.

- You can also visit our website : www.lgappliances.com or call 1-877-714-7481.

- 7 -

HOW TO INSTALL REFRIGERATOR

Test Switch

Confirm the amount

of water

Ice maker

Too much

Too little

Optimum level

3. How to Control the Amount of Water Supplied to Icemaker.

3-1. Confirm the amount of water supplied to the icemaker.

1. Pull out the ice bin shelf in the upper part of the freezer compartment.

Caution : • Do not put hands or tools into the chute to confirm

the operation of geared motor. It may damage the refrigerator or hurt your hands.

2. Apply electricity after connecting water pipe.

1) Press test switch under the icemaker for two seconds as shown below.

2) The bell rings(ding~dong) and ice tray rotates and water comes out from the icemaker water tube.

3) The water shall be supplied two or three times into the tray. The amount of water supplied for each time is small. Put a water container under the ice tray and press test switch.

4) When ice tray rotates, the water in it will spill. Collect the spilt water and throw away into the sink.

5) When ice tray has finished rotation, water comes out from the water tube. Confirm the amounts of water in the ice tray. (refer to fig. The optimum amount of water is 110cc)

* It is acceptable if the adjusted level of water is a bit smaller than optimum level.

- 8 -

HOW TO INSTALL REFRIGERATOR

Conrm the amount

of water

Optimum level

3-2. Control the amount of water supplied to the icemaker.

Caution : • Please unplug the power cord from the wall outlet and wait for more than three minutes before disconnecting

PWB cover as 310V is applied in the control panel.

1. Disconnect PWB cover from the upper part of the refrigerator.

2. Adjust the amount of water supplied by using DIP switch.

Water Supplying Time Control Option

LSC27926**

DIP SWITCH SETTING

S1 S2 S3

OFF OFF OFF 6.5 SEC

ON OFF OFF 5.5 SEC

OFF ON OFF 6 SEC

ON ON OFF 7 SEC

OFF OFF ON 7.5 SEC

ON OFF ON 8 SEC

OFF ON ON 9 SEC

ON ON ON 10 SEC

WATER

SUPPLY TIME

* The quantity of water

supplied depends on DIP switch setting conditions and water pressure as it is a direct tap water connection type. (the water supplied is generally 80 cc to 120 cc)

* DIP switch is on the main

PWB.

(+) Driver

REMARKS

1) The water supplying time is set at ve seconds when the refrigerator is delivered.

2) The amount of water supplied depends on the setting time and water pressure (city water pressure).

3) If ice cube is too small, increase the water supplying time. This happens when too small water is supplied into the ice tray .

4) If ice cube sticks together, decrease the water supplying time. This happens when too much water is supplied into the ice tray.

Caution : When adjusting the amount of water supplied, adjust step by step. Otherwise the water may spill over.

Switch ON

Switch OFF

2 3

3. When adjustment of control switch for the amount of water supplied is complete, check the level of water in the ice tray.

- 9 -

MICOM FUNCTION

1. Monitor Panel

ICE PLUS DISPENSER FREEZER REFRIGERATOR LIGHT/FILTER ALARM/LOCK 3SECS

°C

°F

Ice Plus

function selection button

Dispenser selection button

Temperature adjustment button for freezer compartment

Alarm button and

Lock button

Lamp On/O button/

Filter status display RESET button

Temperature adjustment button

for refrigerator compartment

- 10 -

1-3. Display Second Function

1. Buzzer sound mute Mode

The buzzer sound is set to OFF. It activates by sounding the recognition sound of “Ding~” after pressing and holding ICE PLUS” button more than 5 seconds. It inactivates when resetting the mode power.

2. Display Power saving Mode

It places display in standby mode until door is opened. Press “Freezer” and ICE PLUS” buttons simultaneously to turn all leds become ON and then OFF with the recognition sound of “Ding~” after 5 seconds. (Be sure not to press only one button to work.) Once the mode activates, the display is always OFF. Until door is opened or display button is pressed. When 30 seconds has elapsed after closing door or pressing button, the display turns OFF. To deactivate this mode is same as the activation methods. The mode inactivates when resetting the power.

3. Change Display Degree to Centigrade Mode from Fahrenheit Mode

To change temperature display from Fahrenheit to Celsius press and hold “FREEZER” and “REFRIGERATOR” buttons simultaneously for more than 5 seconds. Do the same to convert back to Celsius.

4. Exhibition Mode

This function is available when exhibiting a refrigerator in the shopping moll. Function is inserted with recognition sound “Ding ~” if pressing both the ICE PLUS” button and the “REFRIGERATOR” button at the same time for more than 5 seconds. If function is inserted, all basic refreezing functions at the R/F room and the Storage room (COMP, F-FAN, C-FAN) turns off and the display normally operates. However, the dispenser function normally operates. The DEMO stops if pressing the button during DISPLAY DEMO, DEMO stops and the display normally operates but performs DEMO operation again if not pressing the button again for more than 30 seconds (DEMO: Display scenario when using the display). Release method is same as input method. The mode is released if power is reset.

MICOM FUNCTION

- 11 -

ICE PLUS/JET FRZ DISPENSER FREEZER REFRIGERATOR FILTER/LIGHT LOCK

Display Power saving Mode

Exhibition Mode

Change Display Degree from Fahrenheit to Centigrade Mode

Buzzer sound mute Mode

°C

°F

MICOM FUNCTION

2. Description of Function

2-1-1. Function of Temperature Selection

Division Power Initially On 1st Press 2st Press 3th Press 4th Press

Setting temperature

Temperature Control

Freezer Control

Refrigeration Control

* The temperature can vary ±3 °C depending on the load condition.

5 4 3 2 1

Medium Medium Max Max Min Medium Min

-2 °F -5 °F -8 °F7 °F1 °F

37 °F 34 °F 32 °F 46 °F 41 °F

5 4 3 2 1

❉ Whenever pressing button, setting is repeated in the order of (Medium) ➝ (Medium Max) ➝ (Max) ➝ (Min) ➝

(Medium Min).

• The actual inner temperature varies depending on the food status, as the indicated setting temperature is a target temperature, not actual temperature within refrigerator.

• Refrigeration function is weak in the initial time. Please adjust temperature as above after using refrigerator for minimum 2~3 days.

• Freezer Notch is fixed “Medium Max” unconcerned with display Notch during ICE Making Control Mode and Ice Maker Stop switch is selected with “ON”.

2-1-2. Outside temperature display function

1. Outside temperature sensor at the right Hinge Cover - U of refrigerator senses ambient temperature and displays the outside temperature in the upper of “ROOM TEMP” text on the display part.

2. Ambient temperature is displayed up to 16°F ~ 120°F and displayed as “Lo” for less than 15°F and as “HI” for more than 121°F. If the ambient temperature sensor fails, it is displayed as “Er”.

3. Since display temperature of outside temperature is temperature sensed by the ambient sensor in the hinge U of the refrigerator room, it may differ from the outside temperature display of other household electrical appliances.

- 12 -

MICOM FUNCTION

2-1-3. Lock function (dispenser and display button lock)

1. In power application of refrigerator, the “LOCK” text is turned o at the right side of lock graphic of display with the lock replease status.

2. If desiring to lock the dislay the dispenser and control panel, push on the LOCK button more than 3 seconds. LOCK text is turned on at the right side of lock graphic of display with lock status.

3. The buzzer sound and control panel and dispenser function is not performed even if pressing display button other than lock key in the lock status.

4. If desiring to release the lock status and pressing the lock button more than 3 seconds. “LOCK ” text is turned o at the right side of lock graphic of display with the lock release status.

LOCK CONTROL

LOCK

DISPENSER & BUTTON

LOCK

DISPENSER & BUTTON

2-1-4. Filter condition display function

1. There is a replacement indicator light for the water lter cartridge on the dispenser.

2. Water lter needs replacement once six months.

3. Water lter light and “FILTER RESET HOLD 3SECS” text turn on to tell you need to replace the lter soon.

4. After replece the lter, press and hold the lock button more than 3seconds. Then water lter light and “FILTER RESET HOLD 3SECS” text turn o with reset status.

Classication

Filter Status

Display

FILTER

FILTER RESET

- 1 3 -

MICOM FUNCTION

DISPENSER

2-2. Dispenser use selection

You can select water or ice.

Please select water, slice ice and square ice by pressing button as you desire.

Please press the push button lightly by catching and pushing in cup.

• Each graphic is indicated for the selected function.

• “Tak! ” sounds if 5 seconds pass after ice comes out. It is sound that the outlet of ice is closed.

REFERENCE :

Please wait for 2-3 second in order to take nal ice slices or drops

of water when taking out cup from the pressing switches after taking ice or water.

DISPENSER

Pressing

Switch

2-3. ICE PLUS

Please select this function for prompt freezer.

• Function is repeated following below whenever pressing ICE PLUS

•

The arrow mark graphic remains at the On status after ickering 4 times when selecting Special Refrigeration ICE PLUS.

•ICE PLUS function automatically turns o

if a xed time passes.

LED

ICE PLUS

2-4. Dispenser Light

• Dispenser switch or dispenser light button turn the dispenser light in the dispenser on and o.

• The dispenser light Function is repeated following below whenever pressing “FILTER RESET/LIGHT” button.

• If dispenser light continuously turns on more than 7 minutes with dispenser light button, the dispenser light turns o automatically by compulsion.

Dispenser Iight ON/OFF

LED

- 1 4 -

MICOM FUNCTION

2-5. ICE PLUS

1. ICE PLUS is function to improve cooling speed of the freezing room by consecutively operating compressors and

freezing room fan.

2. ICE PLUS is released if power failure occurs and then returns to the original status.

3. Temperature setting is not changed even if selecting the ICE PLUS.

4. The change of temperature setting at the freezing room or the cold storage room is allowed with ICE PLUS

selected and prrocessed.

5. The cold storage room operates the status currently set with ICE PLUS selected and procesed.

6. If selecting the ICE PLUS, the ICE PLUS function is released after continuously operating compressor and

freezing room fan.

7. If frost removal starting time is arrived during ICE PLUS, ICE PLUS operation is done only for the remaining

time after completion of frost removal when the ICE PLUS operation time passes 90 minutes. If passing 90 minutes, ICE PLUS operation is done only for 2 hours after completion of frost removal.

8. If pressing ICE PLUS button during frost removal, the ICE PLUS LCD or LED is turned on but if pressing the

ICE PLUS, compressor operates after the remaining time has passed.

9. If selection ICE PLUS within 7 minutes (delay for 7 minutes of compressor) after the compressor stops,

compressor operates after the remaining time has passed.

10. The freezing room fan motor operates at the high speed of RPM during operation of ICE PLUS.

- 15 -

MICOM FUNCTION

Doors of freezing / cold storage room

or home bar

BUZZER

Closing

Opening

Within

a minute

A minute

seconds30seconds30seconds

Opening

Closing Closing

3 Times 3 Times 3 Times 3 Times

2-8. Control of variable type of freezing fan

1. To increase cooling speed and load response speed, MICOM variably controls freezing room fan motor at the high speed

of RPM and standard RPM.

2. MICOM only operates in the input of initial power or ICE PLUS operation or load response operation for the high

speed of RPM and operates in the standard RPM in other general operation.

3. If opening doors of freezing / cold storage room or home bar while fan motor in the freezing room operates, the freezing

room fan motor normally operates (If being operated in the high speed of RPM, it converts operation to the standard RPM). However, if opening doors of freezing room or home bar, the freezing room fan motor stops.

4. As for monitoring of BLDC fan motor error in the freezing room, MICOM immediately stops the fan motor by determining

that the BLDC fan motor is locked or poor if there would be position signal for more than 115 seconds at the BLDC motor. Then it displays failure (refer to failure diagnosis function table) at the display part of refrigerator, the BLDC motor doesn’t operate more. If you want to operate the BLDC motor, turn off and on power resource.

2-9. Control of cooling fan motor

1. The cooling fan motor performs ON/OFF control by linking with the COMP.

2. It controls at the single RPM without varying RPM.

3. Failure sensing method is same as in fan motor of freezing fan motor (refer to failure diagnosis function table for failure

display).

2-10. Door opening alarm

1. Buzzer generates alarm sound if doors are not closed even when more than a minute consecutively has passed with

doors of freezing / cold storage room or home bar opened.

2. Buzzer rings three times in the interval of 0.5 second after the first one-minute has passed after doors are opened and

then repeats three times of On/Off alarm in the cycle of every 30 seconds.

3. If all the doors of freezing / cold storage room or home bar are closed during door open alarm, alarm is immediately

released.

2-11. Ringing of button selection buzzer

1. If pressing the front display button, “Ding ~ “ sound rings.

- 16 -

MICOM FUNCTION

2-12. Ringing of compulsory operation, compulsory frost removal buzzer

1. If pressing the test button in the main PCB, “Phi ~” sound rings.

2. In selecting compulsory operation, alarm sound is repeated and completed in the cycle of On for 0.2 second and Off for

1.8 second three times.

3. In selecting compulsory frost removal, alarm sound is repeated and completed in the cycle of On for 0.2 second , Off for

0.2 second, On for 0.2 second and Off for 1.4 second three times.

2-13. Frost removal function

1. Frost removal is performed whenever total operation time of compressor becomes 7 ~ 7.5 hour.

2. In providing initial power (or returning power failure), frost removal starts whenever total operation time of compressor

becomes 4 ~ 4.5 hour.

3. Frost removal is completed if temperature of a frost removal sensor becomes more than 5°C after starting frost removal.

Poor frost removal is not displaced if it does not arrive at 5°C even if two hours have passed after starting frost removal.

4. No removal is done if frost removal sensor becomes poor (snapping or short-circuit).

2-14. Refrigerator room lamp automatically off

• Refrigerator room lamp turn on and off by refrigerator door switch.

• If refrigerator room lamp continuously turns on more than 7 minutes, the refrigerator room lamp turns off automatically by

compulsion.

- 17 -

MICOM FUNCTION

POWER

COMP

F-FAN

C-FAN

R-STEP MOTOR

DAMPER

OPTICHILL

STEP

DAMPER

MOTOR

FROST

REMOVAL

HEATER

OFF

FROST

REMOVAL

HEATER

DAMPER

DUCT DOOR

OPTICHILL

HEATER ON

DAMPER

DUCT DOOR

OPTICHILL

HEATER OFF

0.3

sec.

6.0

sec.

0.3

sec.

0.3

sec.

0.3

sec.

POWER

0.3

sec.

PIPE

DISP'

HEATER

OFF

0.3

sec.

COMP

0.3

sec.

F-FAN

C-FAN

0.3

sec.

R-STEP MOTOR

DAMPER

0.3

sec.

OPTICHILL

STEP

DAMPER

MOTOR

PIPE

DISP'

HEATER

TEST

SWITCH

(PRESS

Once)

OTHER

LOAD

OFF

COMP

F-FAN

C-FAN

R-STEP MOTOR

DAMPER

OPTICHILL

STEP

DAMPER

MOTOR

TEST

SWITCH

(PRESS

2 Times)

COMP

OFF

F-FAN

C-FAN

OFF

FROST

REMOVAL

HEATER

R-STEP MOTOR

DAMPER

0.3

sec.

0.3

sec.

0.3

sec.

0.3

sec.

0.3

sec.

0.3

sec.

0.3

sec.

0.3

sec.

0.3

sec.

0.3

sec.

0.3

sec.

2-15. Sequential operation of built-in product

Built-in products such as compressor, frost removal heater, freezing room fan, Cooling Fan and step motor damper are

sequentially operated as follows for preventing noise and part damage occurred due to simultaneous operation of a lot of

parts in applying initial power and completing test.

Function Load Operation Sequence Remark

In applying Initial power TEST MODE

When temperature of a frost removal

sensor becomes more than 45°C (In purchase,

movement)

When temperature of a

frost removal sensor becomes less than 45°C (In power failure,

service)

Test mode 1 (Compulsory function)

Test mode 2 (Compulsory frost

removal)

If error occurs during operation, initial operation is not done.

■

Sequence of load operation when closing F-room and R-room.

If pressing switch once more in the test mode 2 or temperature of a frost removal sensor is more than 5°C, it immediately returns to the test mode for initial operation (COMP operates after 7 minutes).

- 18 -

MICOM FUNCTION

Note1) R2-sensor, OptiChill sensor and water tank sensor, Ice maker-sensor, Ice maker Unit are not indicated on the failure

indicating part but indicated in checking Display(When pressing for more than the button of freezing temperature and super freezer button for more than 1 second).

R2-sensor (middle room) or Abnormal Drive Micom Communication

OptChill sensor or Water tank sensor

Ice-maing sensor

Ice-maker unit

Ambient sensor (Better1 Model Only)

Note2) Freezer room notch temperature display and refrigerator room notch temperature display(Failure code indication

part) are normally indicated in abnormal ambient sensor, and “Er” indicated on the amvient temperature display(except for the ambient temperature display, other LEDs or LCDs are indicated normally)

✻ LCD(LED) check function: If simultaneously pressing express freezer button and freezing temperature adjustment button

for a second, a back light is turned on and all display LCD(LED) graphics on. If releasing the button, the LCD(LED) graphic displays the previous status, the back light is turned off (LCD graphic and back light ON/OFF check).

Normal: LED or LCD graphic on the (C) part turns on Abnormal: LED or LCD graphic on the (C) part turns off

Normal: LED or LCD graphic on the (D) part turns on Abnormal: LED or LCD graphic on the (D) part turns off

Normal: LED or LCD graphic on the (E) part turns on Abnormal: LED or LCD graphic on the (E) part turns off

Normal: LED or LCD graphic on the (F) part turns on Abnormal: LED or LCD graphic on the (F) part turns off

Normal: LED or LCD graphic on the (G) part turns on Abnormal: LED or LCD graphic on the (G) part turns off

The other LED or LCD Graphics Turn On.

- 20 -

MICOM FUNCTION

2-17. Test Function

1. The purpose of test function is to check function of the PWB and product and to search for the failure part at the failure

status.

2. Test button is placed on the main PCB of refrigerator (test switch), and the test mode will be nished after maximum 2

hours irrespective of test mode and then is reset to the normal status.

3. Function adjustment button is not perceived during performance of test mode.

4. In nishing test mode, always pull the power cord out and then plug-in it again for the normal state.

5. If nonconforming contents such as sensor failure are found during performance of test mode, release the test mode and

display the failure code.

6. Even if pressing the test button during failure code display, test mode will not be performed.

skrameRstnetnoCnoitarepOedoM

Test 1

Test 2

Normal

Status

Press test button once (strong cold mode)

Press test button once at the test mode 1 status (forced defrost mode)

Press test button once at the test mode 2 status

1. Continuous operation of compressor

2. Continuous operation of freezing bldc motor (high-speed RPM) and cooling bldc motor

3. Defrost heater turns o

4. Stepping motor damper is completely opened (open of bae)

5. Optichil stepping motor damper is completely closed.

6. All display LEDs or LCD graphics turn on.

1. Compressor OFF

2. Freezing bldc motor and cooling bldc motor turn o

3. Defrost heater turns on

4. Stepping motor damper is completely closed (closing of bae)

5. OptiChil stepping motor damper is completely closed.

6. All display LEDs or LCD graphics turn o. GR-L267BV(T)RA, GR-L267BV(T,S)PA : Except for (A)22 (B)22 LEDs GR-L267BV(T)R : Except for only middle Notch Bar Graphics

Return to the initial status.

Freezing fan turns o in door opening.

Return to the normal mode when the defrost sensor is above +5 °C

Compressor will operate after delay for 7 minutes

TEST MODE1 STATUS DISPLAY

°F

TEST MODE2 STATUS DISPLAY

- 2 1 -

MICOM FUNCTION

2-18. Function of dispenser and water dispenser built-in

1. This is function allowing ice and water to come outside without opening door.

2. If pressing the dispenser switch (rubber button) after selecting ice (cube ice, crushed ice) or water, ice and water equivalent to each come out. However, the duct doors are opened by electrical solenoid valve (Duct Door Solenoid) if pressing the press switch in case of selecting ICE. If pressing the dispenser press switch and then detaching the hands, the duct door is closed after it is opened for 5 seconds.

3. Function allowing ice and water to come stops if freezing room doors are opened.

4. If there is no Off signal even when 3 minutes have passed while pressing the dispenser press switch after selecting ice (cube ice, crushed ice) or water, geared motor and solenoid (Cube, Water) is automatically turned off. However, the solenoid (duct door) is stop 5 seconds after Off (to prevent short-circuit of a coil due to overheat of solenoid).

5. Dispenser Lamp On/Off function Lamp on the dispenser part is turned on if pressing the dispenser press switch after selecting ice (cube ice, crushed ice) or water. If detaching the hands, it is turned off.

6. Selection function of water/crushed/ cube ice

1) This is function to allow selection of water/crushed/ cube ice function depending on user’s selection. Display and selection is done if pressing the dispenser selection button.

2) In the initial Power On, cube ice is automatically selected.

3) In selecting cube ice, geared motor is operated so that crushed ice can be supplied outside if pressing the press switch when ice is formed in the ice storage container (Bank, Ice).

4) In selecting cube ice, geared motor is operated so that cube ice can be supplied outside if pressing the press switch when ice is formed in the ice storage container (Bank, Ice).

7. Water dispenser function

1) It is displayed for selection if user selects water at the function adjustment part.

2) Water dispenser function is a type directly connected to a water pipe. The water solenoid valve built-in at the right side of the Back plate is opened so that water can be supplied if selecting Water from the function adjustment part and then pressing the press switch.

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EXPLANATION FOR MICOM CIRCUIT

1. Explanation for PWB circuit

1-1. Power circuit

The power

to DC, a switch (IC2) switching the DC voltage, a transformer, and a feedback circuit (IC3 and IC4).

Caution : Since high voltage (160 Vdc) is maintained at the power terminal, wait at least 3 minutes after unplugging the

Voltage of every part is as follows:

circuit includes a Switched Mode Power Supply (SMPS). It consists of a rectier (BD1 and CE1) converting AC

appliance to check the voltages to allow the current to dissipate.

Part VA1 CE1 CE2 CE3 CE4 CE5

Voltage 120 Vac 160 Vdc 14 Vdc 12 Vdc 15.5 Vdc 5 Vdc

- 2 3 -

1-3. Reset circuit

The RESET circuit allows various parts of the MICOM, such as RAM, defrosting, etc., to be restarted from the initial state when power is interrupted or restored. A LOW signal applied to the reset terminal for 10 ms causes the MICOM to reset itself. During normal operation, the voltage at the reset terminal is 5 Vdc. If the reset fails, the MICOM will not operate.

1-4. Load/dispenser operation, door opening circuit

1. LOAD DRIVING CIRCUIT

The fan operates at the regular speed even if the door of the refrigerator or freezer is opened. When the doors are closed, the fan reverts to its original speed.

(A), (B), (C), and (D) of door switch for the freezer or refrigerator are connected to the door open sensing circuit in paralle toward both ends of switch to determine door open at MICOM.

In the TEST mode, the fan will stop if any door is opened. It will resume operation when the door is closed.

Type of Load Compressor

Measuring part (IC6) IC6-16 IC6-13 IC6-12 IC6-15 IC6-14

Status

1) Check load driving status

Type of Load

Measuring part IC6-11 IC6-10 IC7-15 IC7-13

Status

2) Lever Switch sensing circuit

Measuring part

Lever S/W

On(Press)

GEARED

MOTOR

Frost Removal

Heater

SOLENOID

CUBE

5 V

0 V

AC Converting

Relay

V1nihtiWNO

V21FFO

V1nihtiWNO

V21FFO

IC1(Micom) (No. 16)

V5FFO

Refrigerator

WATER VALVE

WATER

LAMP

SOLENOID

DISPENSER

(60 Hz)

Dispensor

Heater

-24-

EXPLANATION FOR MICOM CIRCUIT

-25-

EXPLANATION FOR MICOM CIRCUIT

3. Door opening sensing circuit

Measuring part

IC1 (MICOM) No. (44, 45) / (45, 46) / (47, 48) Pin

Door of Freezer / Refrigerator

Since door switches (A) and (B) are interconnected, if either fails, the other will not respond properly. If either switch fails, the light will not come on.

)sutatsffOtaerasdnehtobtahctiwS.D-C,B-A(V5gnisolC

)sutatsnOtaerasdnehtobtahctiwS.D-C,B-A(V0gninepO

- 26 -

EXPLANATION FOR MICOM CIRCUIT

RW1

10KF

CE18

R73

CC32

1-5. Temperature sensing circuit

1-6. Switch entry circuit

The following circuits are sensing signal form the test switch, damper motor reed switch for testing and diagnosing the refrigerator.

- 27 -

EXPLANATION FOR MICOM CIRCUIT

1-7. Option designation circuit (model separation function)

The circuits shown above vary according to which features are included on your particular model.

These circuits are preset at the factory and cannot be altered.

•

NOTE: The chart makes absolutely no sense. You have Optichill no matter which way the connection is set.

OP1

1-8. Stepping motor operation circuit

dradnatSnoitacilppAsutatSnoitcennoCnoitarapeS

tsixellihCitpOnoitcennoC

nodllihCitpOTUO ’t exist

-28-

EXPLANATION FOR MICOM CIRCUIT

INA

INB

WC )noitator evitisoP()noitator esreveR( WCC

The motor is driven by magnetism formed in the areas of the coils and the stator. Rotation begins when a HIGH signal is applied to MICOM Pin 33 of IC10 (TA7774F). This causes an output of HIGH and LOW signals on MICOM pins 34 and 35.

Explanation) The stepping motor is driven by sending signals of 3.33 mSEC via MICOM pins 33, 34, and 35, as shown in

the chart below. These signals are output via terminals 10, 11, 14, and 15 via input terminals 3, 6, and 8 of IC10 (TA7774F), the motor drive chip. The output signals allow the coils wound on each phase of the stator to form a magnetic eld, which causes rotation. Input to the terminals INA and INB of IC10 as shown in the chart below drives the motor.

-29-

EXPLANATION FOR MICOM CIRCUIT

1-9. Fan motor driving circuit (freezer, mechanical area)

1. The circuit cuts all power to the fan drive IC, resulting in a standby mode.

2. This circuit changes the speed of the fan motor by varying the DC voltage between 7.5 Vdc and 16 Vdc.

3. This circuit stops the fan motor by cutting o power to the fan when it senses a lock-up condition.

trapetrapbtrapd,a

sselroV2sselroV2V5FFOrotoM

V61~8V41~21V3~2NOrotoM

-30-

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