LG WM3997H A /01 Series User manual

WASHING MACHINE
SERVICE MANUAL
CAUTION
READ THIS MANUAL CAREFULLY TO DIAGNOSE
PROBLEMS CORRECTLY BEFORE SERVICING THE UNIT.
MODEL :WM3997H*A /01
Any reproduction, duplication, distribution (including by way of email, facsimile or other electronic means),
publication, modification, copying or transmission of this Service Manual is STRICTLY PROHIBITED unless you
have obtained the prior written consent of the LG Electronics entity from which you received this Service
Manual. The material covered by this prohibition includes, without limitation, any text, graphics or logos in this
Service Manual.
Copyright © 2016~ 2017 LG Electronics Inc. All rights reserved. Only training and service purposes.

69
MFL67307985
PRINTED IN KOREA

[
CONTENTS
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reserved. Only training and service purposes.

DOOR FRAME Chrome
12A
WARNING:
Wash hands after handling
WM3997H*A /01
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reserved. Only training and service purposes.

6
2. FEATURES & TECHNICAL EXPLANATION
2-1. FEATURES
Ultra Capacity
The larger drum enables not just higher head drop and stronger centrifugal force,
but also less tangling and wrinkling of the laundry. Heavier loads, such as king size
comforters, blankets, and curtains, can be washed.
Direct Drive System
The advanced brushless DC motor directly drives the drum without belt and pulley.
Tilted Drum and Extra Large Door Opening
Tilted drum and extra large opening make it possible to load and unload clothing
more easily.
Steam Washing
Steam washing features upgraded washing performance with low energy and water
consumption.
Automatic Wash Load Detection
Automatically detects the load and optimizes the washing time.
Built-in Heater
Internal heater helps to maintain water temperature at its optimum level for selected
cycles.
Child Lock
The child lock prevents children from pressing any button to change the settings
during operation.
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7
2-2. NEURO FUZZY WASHING TIME OPTIMIZATION
To get the best washing performance, optimal time is determined by the water temperature,
the selected washing temperature, and the size of the load.
2-3. WATER LEVEL CONTROL
This model incorporates a pressure sensor which can sense the water level in the tub.
The water supply is stopped when the water level reaches the preset level, the washing
program then proceeds.
Spinning does not proceed until the water in the tub drains to a certain level.
water
temperature
washing time
rinsing time
the best
washing
performance
spin rhythm, time
load
size
NEURO-
FUZZY
selected
washing
temperature
SENSING EFFECT PROCESSING DETERMINATION
The door can be opened by pulling the door handle whenever washer is not in operation.
When the cycle is completed, the DOOR LOCKED light will turn off.
If a power failure has occurred while in operation, the door will unlock after 5 minutes.
Clicking sounds can be heard when the door is locked/unlocked.
2-4. DOOR CONTROL
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8
2-5. THE DOOR CAN NOT BE OPENED
While program is operating.
When a power failed and power plug is taken out in operation.
While Door Lock lights turn on.
White the motor is in the process of inertial rotating, through the operation is paused.
2-6. DOOR LOCKED LAMP LIGHTS
When the frequency of water level is lower than 22.9 kHz.
(It can be canceled when the frequency is more than 23.8 kHz.)
When the temperature inside the tub is higher than 45°C and water level is not 25.5 kHz.
(It can be canceled when the water level is 25.5 kHz or the temperature inside the tub is lower than 40°C.)
2-7. CHILD LOCK
Use this option to prevent unwanted use of the washer. Press and hold Pre Wash button for 3
seconds to lock/unlock control.
When child lock is set, CHILD LOCK lights and all buttons are disabled except the POWER
button. You can lock the controls of the washer while washing.
CHILD LOCK lasts after the end of cycle. If you want to deactivate this function,
Press and hold the Pre Wash button for 3 seconds.
2-8. WATER CIRCULATION
When washing and rinsing function of shower at the upper part of Gasket.
When washing, it continuously operates for 3 minutes and intermittently.
When rinsing, it continuously operates after completion of water supply.
2-9. STEAM
For tough stained clothes, sick room linens, or baby clothes.
Steam Wash is available with Sanitary, Bulk/Large, Perm. Press, Cotton/Normal, and Baby Wear cycles.
This option features upgraded washing performance with low energy and water consumption.
Do not load delicates such as wool, silk, and easily discolored clothes.
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reserved. Only training and service purposes.

3. PARTS IDENTIFICATION
Accessories
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10
1
2
3
4
5
6
7
Before servicing, ask the customer what the trouble is.
When installing or repairing the washer, put on long gloves and safety glasses.
Check the setup (power supply is 120 V
AC, remove the transit bolts, level the washer, etc.)
Check with the troubleshooting guide.
Plan your service method by referring to the disassembly instructions.
Service the unit.
After servicing, operate the appliance to see whether it functions correctly.
STANDARD INSTALLATION
The appliance should be installed as follows:
Remove the 4 shipping bolts
with the supplied wrench.
Remove the lower boits fist.
It is easier that way.
Keep the shipping bolts and
spanner for future use.
Insert the 4 caps (provided)
into the hole.
Turn clockwise to raise;
counterclockwise to lower.
Turn the leveling feet to
adjust the appliance.
Lower
Higher
REMOVE THE SHIPPING
BOLTS
INSTALL THE APPLIANCE
ON A FLAT AND FIRM SURFACE
ADJUST THE
LEVELING
4. INSTALLATION & TEST
Keeping
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11
Verify that the rubber washer is inside of the
valve connector.
Tighten the inlet hose securely to prevent leaks.
Install the inlet hose to correct temperature
water tap.
Otherwise, it cause drips on the drawer panel
handle and drawer panel.
HOW TO CONNECT THE INLET HOSE
CONNECT THE DRAIN HOSE
•Make sure that the hose is not twisted.
CONNECT POWER PLUG
The end of the drain hose should be placed less than 96” from the floor.
•Avoid submerging the end of the hose.
•Connect the power plug to the wall outlet.
•Avoid connecting several electric devices,
as doing so may cause a fire.
Hot Cold
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12
7TEST OPERATION
1Preparation for
washing.
•Connect the power plug to the
outlet.
•Connect the inlet hoses.
2Press the POWER button. 3Press the START/PAUSE
button.
•Listen for a click to determine if the
door has locked.
6Check the water heating
function.
•Press the WASH/RINSE button
and the present temperature will
be displayed.
•Check if the drum rotates
clockwise and counterclockwise.
5Check the automatic reverse
rotation.
4Check the water supply.
•Check if water is supplied through
the detergent dispenser.
7Check the drain and spin
functions.
•Power off and the power on.
•Press the SPIN SPEED button.
•Press the START/PAUSE button.
•Check the spin and drain functions.
•Listen for a click to determine if the
door is unlocking.
8Press the START/PAUSE
button.
9Water removal
•If SERVICE is needed during
check, remove the remaining
water by pulling out the hose cap.
LGE Internal Use Only Copyright © 2016 ~ 2017 LG Electronics Inc. All rights
reserved. Only training and service purposes.

LGE Internal Use Only Copyright © 2016 ~ 2017 LG Electronics Inc. All rights
reserved. Only training and service purposes.

LGE Internal Use Only Copyright © 2016 ~ 2017 LG Electronics Inc. All rights
reserved. Only training and service purposes.

Wash Temp./Spin Speed/S o i l L e v e l Button
DRY
Cold Wash : Use this option to save on energy consumption.
Delay Wash : Set the delay time of starting the cycle.
Custom PGM : Use this option to save a special combination of settings that you use
frequently
Wash Temp. : Selects the water temperature for the wash
cycle
Spim Speed : Selects the spin speed
Soil Level : Selects a wash cycle by soil level.
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reserved. Only training and service purposes.

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reserved. Only training and service purposes.

17
7. TEST MODE
SPIN SPEED SOIL LEVEL
WASH/RINSE DELAY WASH
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reserved. Only training and service purposes.

18
8. TROUBLESHOOTING
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reserved. Only training and service purposes.

19
ESUACMOTPMYSRORRE
LOCKED MOTOR
ERROR
EEPROM ERROR
• The connector (3-pin, male, white) in the MOTOR
HARNESS is not connected to the connector (3-pin,
female, white) of STATOR ASSEMBLY.
• The electric contact between the connectors (3-pin,
male, white) in the MOTOR HARNESS and 4-pin,
female, white connector in the MAIN PWB
ASSEMBLY is bad or unstable.
• The MOTOR HARNESS between the STATOR
ASSEMBLY and MAIN PWB ASSEMBLY is cut
(open circuited).
•
8
• EEPROM is out of order.
Displayed only when the START/PAUSE button is
first pressed in the Load Test Mode.
9
gnihsawelihwdeppotssiylppusrewopehtretfA•ERULIAFREWOP
machine is working, the power is supplied rapidly.
10
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20
Is the supplied voltage 120V AC?
Is the voltage between the 2 FILTER ASSEMBLY
connectors 120V AC?
Is the LED (1) on?
Are the connectors (2) on the PWB loose?
Is wire of the DISPLAY PWB ASSEMBLY
broken?
Replace DISPLAY PWB ASSEMBLY
or repair wire.
Check the fuse or reset
the circuit breaker.
Replace the FILTER
ASSEMBLY (CIRC).
Replace MAIN PWB
ASSEMBLY.
Reconnect.
Replace the MAIN PWB
ASSEMBLY.
NO POWER
8-3. FAULT DIAGNOSIS AND TROUBLESHOOTING
1.Be careful of electric shock if disconnecting parts while troubleshooting.
2.First of all, check the connection of each electrical terminal with the wiring diagram.
3. If you replace the MAIN PWB ASSEMBLY, reinsert the connectors correctly.
CAUTION
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reserved. Only training and service purposes.

21
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