LG STEAM WASHER WM0742H*A User manual

WASHING MACHINE
SERVICE MANUAL
CAUTION
READ THIS MANUAL CAREFULLY TO DIAGNOSE TROUBLES
CORRECTLY BEFORE OFFERING SERVICE.
Website: http: //www.LGEservice.com
E-mail: http: //www.LGEservice.com/techsup.html
MODEL : WM0742H*A

40
SEP. 2007 PRINTED IN KOREA P/No.: MFL30599116

2
CONTENTS
1. SPECIFICATION ............................................................................................................................... 3
2. FEATURES & TECHNICAL EXPLANATION .................................................................................... 4
3. PARTS IDENTIFICATION ................................................................................................................. 7
4. INSTALLATION & TEST ................................................................................................................... 8
5. OPERATION ................................................................................................................................... 11
6. WIRING DIAGRAM/PROGRAM CHART ........................................................................................ 14
7. TROUBLE SHOOTING ................................................................................................................... 15
7-1. BEFORE PERFORMING SERVICE ........................................................................................ 15
7-2. QC TEST MODE ...................................................................................................................... 15
7-3. HOW TO CHECK THE WATER LEVEL FREQUENCY ........................................................... 15
7-4. ERROR DISPLAY ..................................................................................................................... 16
8. ERROR DIAGNOSIS AND CHECK LIST ....................................................................................... 18
8-1. DIAGNOSIS AND SOLUTION FOR ABNORMAL OPERATION ............................................. 18
8-2. FAULT DIAGNOSIS AND TROUBLESHOOTING ................................................................... 21
9. DISASSEMBLY INSTRUCTIONS ................................................................................................... 29
10. EXPLODED VIEW .......................................................................................................................... 37
10-1. CABINET & CONTROL PANEL ASSEMBLY ......................................................................... 37
10-2. DRUM & TUB ASSEMBLY .................................................................................................... 38
10-3. DISPENSER ASSEMBLY ...................................................................................................... 39

3
1. SPECIFICATION
ITEM
COLOR
WM0742H*A
POWER SUPPLY
PRODUCT WEIGHT
Cycles
WASH/RINSE TEMPERATURES
SPIN SPEEDS
OPTIONS
WATER CIRCULATION
OPERATION WATER PRESSURE
CONTROL TYPE
WASH CAPACITY [cu.ft]
DIMENSIONS
DELAY WASH
DOOR SWITCH TYPE
WATER LEVEL
LAUNDRY LOAD SENSING
ERROR DIAGNOSIS
AUTO POWER OFF
CHILD LOCK
RLM ENABLE
STEAM
ELECTRICITY
CONSUMPTION
WASHING
DRAIN MOTOR
WASH HEATER
REVOLUTION
SPEED
WASH
SPIN
46 rpm
0-1200 rpm
9
5
5
PRE-WASH, STAIN CYCLE, STEAM, EXTRA RINSE,
RINSE+SPIN, DELAY WASH
Incorporated
14.5-116 psi (100-800 kPa)
Electronic
3.63 (4.2 IEC)
27" (W) X 29 3/4" (D) X 3811/16 (H), 5013/16" (D, door open)
up to 19 hours
PTC + Solenoid
10 steps (by sensor)
Incorporated
Incorporated
Incorporated
Incorporated
-
Incorporated
280 W
80 W
1000 W
AC 120 V, 60 Hz
192 lbs (87kg)
W:BLUE WHITE, G:PEARLY GRAY

4
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 and SteamFreshTM
Steam Washing features upgraded washing performance with low energy and water
consumption. SteamFreshTM cycle removes wrinkles from dry clothes.
RollerJets
Washing ball enhances the wash performance and reduces damage to the clothing.
The jets spray and help tumble clothes to enhance washing performance while
maintaining fabric care.
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.

5
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
2-4. DOOR CONTROL
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.

6
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 intertial 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 You can lock the washer
while it is operating.
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, underwear, 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.
2-10. DRUM LIGHT
The Drum Light comes on when the Power button is pressed. It goes off when the door is closed
and the washer starts operation.
The Drum Light remains off when the door is locked.
The Drum Light can be turned on while the washer is in operation by pressing the Rinse+Spin
button for 3 seconds. The light will turn off automatically 4 minutes later.
The Drum Light comes on when the washing cycle is finished and goes off 4 minutes later.

7
3. PARTS IDENTIFICATION
Control Panel
Drum
Lower cover Cap
Drain Pump Filter
Drain Plug
Shipping Blots
Power Plug
Adjustable Feet
If the supply cord is
damaged, it must be
replaced by the
manufacturer or its
authorized service
technician in order to
avoid a hazard.
Included Accessories
Hot and Cold
Water Hoses
Caps (4)
(for covering
shipping bolt holes)
Wrench
(for removing
shipping bolts and
adjusting leveling feet)
Tie Strap
(for securing
drain hose)
Elbow Bracket
(for securing
drain hose)
Drain Hose
Door
Dispenser
Back of Washer
Air Vent for Safety
Cold Water Inlet
Hot Water Inlet

8
4. INSTALLATION & TEST
1
2
3
4
5
6
Before servicing, ask the customer what the trouble is.
Check the setup (power supply is 120 V AC, remove the transit bolts....).
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.
Do first lower side to remove
easily.
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

9
Verify that the rubber washer is inside of the
valve connector.
Tighten the inlet hose securely to prevent leaks.
HOW TO CONNECT THE INLET HOSE
CONNECT 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.

10
7TEST OPERATION
1Preparation for
washing.
·Connect the power plug to the
outlet.
·Connect the inlet hose.
2Press the POWER button. 3Press the Start/Pause button.
·Listen for a clicking sounds to
determine if the door has locked.
6Check the water heating
function.
·Press the WASH / RINSE button
and the present temperature will
be displayed.
·Make sure that the drum rotates
clockwise and counterclockwise.
5Check the automatic
reversing rotation of the
drum.
4Check the water supply.
·Verify that if water is supplied
through the detergent dispenser.
7Check the drain and spin
functions.
·Press the POWER button twice to
restart.
·Press the SPIN SPEED button.
·Press the START / PAUSE button.
·Check the drain and spin functions.
8Press the START / PAUSE
button.
9Water removal.
·If SVC is needed during check,
remove the remaining water by
pulling out the hose cap.
·Listen for clicking sounds to
determine if the door is unlocking.

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5. OPERATION
WM0742H*A
STEAM

12
STEAMSTEAM
Power Button
•Use this button to turn the
power On/Off.
START/PAUSE button
•Use this button to
Start/stop the washer.
EST.TIME REMANING
•This display shows :
a) the estimated time remaining in the cycle when operating.
b) an error code when an error has been detected.
OPTION button
•Select a water temperature based on the type of
load you are washing.
•To change the spin speed, select the Spin
Speed button until the desired setting is
displayed.
•To change the soil level, select the Soil Level
button until the desired setting is displayed.
CHILD LOCK
•Use this option to prevent unwanted
use of the washer.
Press and hold Quick Cycle and
Delay Wash button for 3 seconds to
lock / unlock control.
•When Child lock is set,‘ ’blinks
and all buttons are disabled but the
Power button. You can thereby lock
the washer while it is operating.

13
STEAM
STATUS INDICATOR
•These lights show elapsed time
of the selected cycle.
BEEPER button
•Choose High/Low/Off.
DOOR LOCKED lamp
•Lights whenever the door is locked.
•The door can be unlocked by
pressing the Start/Pause button to
stop the washer.
CYCLE SELECTOR knob
•Rotate the Cycle selector
knob to select the cycle
designed for different types
of fabric and soil levels.
WASH/RINSE temp. SPIN SPEED,
SOIL LEVEL button
•Prewash:Use this option for loads that need
pretreatment.
It adds 16 minutes prewash and drain.
•Stain Cycle: Adds time to the wash and rinse cycles
for better stain removal. Automatically
provides a rinse.
•Extra Rinse : This option provides an additional
rinse cycle.
•Rinse+Spin : Use this option to rinse and then spin.
•Delay Wash : Allows the start of any cycle to be
delayed for 1~19(12, 9) hours.
CUSTOM PROGRAM button
•Allows you to store a customized wash cycle for
future use.
•To create a Custom Program :
1) Select a cycle.
2) Select the other desired Wash / Rinse Temp.,
Spin Speed, Soil Level.
3) Select the desired Options.
4) Press and hold the Custom Program button for 3
seconds (2 beep sounds).
5) Press the Start/Pause button.
The Custom Program is now stored for future use.
•To reuse the program, select Custom Program and
press Start/Pause.

14
6. WIRING DIAGRAM/PROGRAM CHART
Base/Line
MEZ31823211

15
7. TROUBLESHOOTING
7-1. BEFORE PERFORMING SERVICE
Be careful of electric shock when disconnecting parts while troubleshooting.
The voltage of each terminal is 120 V AC and DC when the unit is plugged in.
7-2. QC TEST MODE
1. Pressing SPIN SPEED and SOIIL LEVEL button simultaneously.
The washer must be empty and the controls must be in the off state.
7-3. HOW TO CHECK THE WATER LEVEL FREQUENCY
Press the WASH/RINSE and DELAY WASH button simultaneously.
2. Press the Power button, while the above condition. Then buzzer will sound twice.
3. Press the Start/Pause button repeatedly to cycle through the test modes.
None
1 time
2 times
3 times
4 times
5 times
6 times
7 times
8 times
9 times
10 times
11 times
12 times
13 times
14 times
15 times
Turns on all lamps and locks the door.
Tumble clockwise.
Low speed Spin.
High speed Spin.
Inlet valve for prewash turns on.
Inlet valve for main wash turns on.
Inlet valve for hot water turns on.
Inlet valve for steam turns on.
Inlet valve for bleach turns on.
Tumble counterclockwise.
Heater turns on for 3 sec.
Circulation pump turns on.
Drain pump turns on.
Water level Sensor for Steam
Steam Heater turns on for 1.2 sec.
Off
rpm (42~50)
rpm (55~65)
rpm (125~135)
Water level frequency (25~65)
Water level frequency (25~65)
Water level frequency (25~65)
Water level frequency (25~65)
Water level frequency (25~65)
rpm (42~50)
Water temperature
Water level frequency (25~65)
Water level frequency (25~65)
Water level frequency of TSG (0~255)
TSG temperature
-
The digits indicate the water level frequency (x. 1 kHz).
So, for example a display indicating 241: a Water level frequency of 241 x.1 kHz
= 24.1 kHz
Number of times the
Start/Pause button is pressed Check Point Display Status

16
7-5. ERROR DISPLAY
If you press the START/PAUSE button when an error is displayed, any error except will
disappear and the machine will go into the pause status.
In case of ,,if the error is not resolved within 20 sec., or the in case of other errors,
if the error is not resolved within 4 min., power will be turned off automatically and the error code will
blink. But in the case of , power will not be turned off.
ERROR SYMPTOM CAUSE
WATER INLET
ERROR
•Correct water level (246) is not reached within 8
minutes after water is supplied or it does not reach
the preset water level within 25 minutes.
1
IMBALANCE
ERROR
•The load is too small.
•The appliance is tilted.
•Laundry is gathered to one side.
•Non distributable things are put into the drum.
2
DRAIN
ERROR •Not fully drained within 10 minutes.
3
OVER FLOW
ERROR
•Water is overflowing (water level frequency is over
213).
If is displayed, the drain pump will operate
to drain the water automatically.
4
PRESSURE
SENSOR
ERROR
•The SENSOR SWITCH ASSEMBLY is out of order.
5
DOOR OPEN
ERROR
•Door not all the way closed.
•Loose electrical connections at Door switch and
PWB Assembly.
•The DOOR SWITCH ASSEMBLY is out of order.
6
HEATING
ERROR •The THERMISTOR is out order.
7

17
ERROR SYMPTOM CAUSE
LOCKED MOTOR
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).
•The hall sensor is out of order/defective.
8
•EEPROM is out of order.
Displayed only when the START/PAUSE button
is first pressed in the QC Test Mode.
9
POWER FAILURE
EEPROM
ERROR
•The washer experienced a power failure.
10

18
8. ERROR DIAGNOSIS AND CHECK LIST
8-1. DIAGNOSIS AND SOLUTION FOR ABNORMAL OPERATION
SYMPTOM GUIDE FOR SERVICE CALL
No power
Water inlet trouble
Is the power plug connected firmly to
120 V AC outlet?
Power failure? or Breaker opened?
Is the outlet controlled by a switch?
Is displayed?
Is the tap opened?
Is the tap frozen?
Is the water supply shut-off?
Visit to service
Is filter in the inlet valve clogged with
foreign material?
Clean the filter of
inlet valve.
YES
NO
YES
YES
NO
NO
NO
YES
Visit to service

19
SYMPTOM GUIDE FOR SERVICE CALL
Door error
Drain trouble
Started with door opened?
Avoid overloading.
Clicking sound is heard once or twice,
when the START/PAUSE button is
pressed to start the cycle?
Visit to service.
Check if the door switch is OK.
NO
YES
YES
NO
YES
NO
NO
YES
NO
Was the load too large?
Is displayed?
Is the drain pump filter clogged with foreign
material such as pins, coins, etc?
Clean
up the
filter
Is the drain hose frozen
kinked, or crushed?
Visit to service.
Close the door.