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Website: http://biz.lgservice.com WASHING MACHINE SERVICE MANUAL CAUTION READ THIS MANUAL CAREFULLY TO DIAGNOSE PROBLEMS CORRECTLY BEFORE SERVICING THE UNIT. MODEL : WM3988H*A Downloaded from www.Manualslib.com manuals search engine...
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AUG. 2007 PRINTED IN KOREA P/No.: MFL30599110 Downloaded from www.Manualslib.com manuals search engine...
1. SPECIFICATIONS ITEM WM3988H*A COLOR W:BLUE WHITE, N:NAVY BLUE POWER SUPPLY AC 120 V, 60 Hz PRODUCT WEIGHT 192 lbs (87kg) WASHING 280 W ELECTRIC POWER DRAIN MOTOR 80 W CONSUMTION WASH HEATER 1000 W WASH 46 rpm REVOLUTION SPEED SPIN 1320 rpm CYCLES...
2. FEATURES & TECHNICAL EXPLANATION 2-1. FEATURES ■ Ultra Capacity The Larger drum enables not just higher head drop and stronger centrifugal force, but 추가선택, 예약, also less tangling and wrinkling of the laundry. Heavier loads, such as king size comforters, blankets, and curtains, can be washed.
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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. water temperature washing time the best selected NEURO- washing washing rinsing time temperature FUZZY...
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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.
4. INSTALLATION & TEST Before servicing, ask the customer what the trouble is. Check the setup (power supply is 120V AC, remove the transit bolts, level the washer..). Check with the troubleshooting guide. Plan your service method by referring to the disassembly instructions. Service the unit.
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■ HOW TO CONNECT THE INLET HOSE Verify that the rubber washer is inside of the valve connector. Tighten the inlet hose securely to prevent leaks. ■ CONNECT THE DRAIN HOSE · Make sure that the hose is not twisted. ·...
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TEST OPERATION Press the POWER button. Press the Start/Pause Preparation for washing. button. • Connect the power plug to • Listen for a click to determine if the outlet. the door has locked. • Connect the inlet hose. Check the water heating Check the automatic Check the water supply.
5. OPERATION 5-1. CONTROL PANEL FEATURES WM3988HWM Downloaded from www.Manualslib.com manuals search engine...
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Power Button Status Indicator • It shows elapsed time of the cycle the washer is • Use this button to turn the power operating. On/Off. Start/Pause Cycle Selector Knob • Use this button to Start/ • Rotate the Cycle selector knob to select the cycle designed for Stop the washer.
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Option Button • PREWASH: Use this option for loads that need pretreatment. It adds 16 minutes prewash and a spin cycle. • RINSE+SPIN: Use this option to rinse and then spin. • EXTRA RINSE: This option provides an additional rinse. •...
5-2. CYCLE GUIDE The cycle guide below shows the options and recommended fabric types for each cycle. Wash/Rinse Pre- Rinse + Extra Stain Water Cycle Fabric type Spin Speed Soil Level Steam Temp. Wash Spin Rinse Cycle Plus Steam Dress shirts, blouses Fresh Extra Hot/Cold High...
5-3. SPECIAL FUNCTIONS The option buttons also activate special functions, including CHILD LOCK, DRUM LIGHT, TUB CLEAN, and LANGYAGE. Press and hold the option button marked with the special function for 3 seconds to activate. CHILD LOCK Use this option to prevent unwanted use of the washer or to keep cycle settings from being changed while the washer is operating.
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LANGUAGE This option allows you to change the language shown in the display. Once set, the selected language will stay set even after the power is turned off. The display language options are English, French, and Spanish; English is the default language. To change the language: Press the ON/OFF button to turn on the washer.
7. TEST MODE 7-1. SAFETY CAUTION There's built-in AC 110V and DC power in output terminal of PWB assembly in common. Be careful electric shock when disconnecting parts while trouble shooting. (Wear Electro Static Discharge gloves when working.) After cutting off the power when changing PWB assembly, disconnect or assemble. Be careful static when handling PWB assembly, and use Electro Static Discharge plastic pack when delivering or keeping it.
7-3. HOW TO READ THE DISPLAY IN LOAD TEST MODE Water level Steam temperature frequency Fan Motor RPM Wash temperature Duct temperature 7-4. HOW TO CHECK THE WATER LEVEL FREQUENCY * Press the WASH/RINSE and SOIL LEVEL button simultaneously. The digits indicate the water level frequency. For example, if the display indicate 058, the water level frequency is 20+(58 X 0.1) = 25,8 kHz.
8. TROUBLESHOOTING 8-1. SAFETY CAUTION There’s built-in AC 120V and DC power in output terminal of PWB assembly in common. Be careful electric shock when disconnecting parts while trouble shooting. (Wear Electro Static Discharge gloves when working.) After cutting off the power when changing PWB assembly, disconnect or assemble. Be careful static when handling PWB assembly, and use Electro Static Discharge plastic pack when delivering or keeping it.
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ERROR SYMPTOM CAUSE • The connector (3-pin, male, white) in the MOTOR LOCKED MOTOR HARNESS is not connected to the connector (3-pin, ERROR 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.
8-4. TROUBLESHOOTING WITH ERROR INLET VALVE ERROR Replace the Is the voltage of the inlet INLET VALVE valve connector 120 V AC? ASSEMBLY. (Check the all terminal of INLET VALVE ASSEMBLY displayed? while the power is on.) When you press both Check the AIR WASH/RINSE button and CHAMBER...
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DRAIN ERROR displayed? Is the coil of the drain Replace the Reconnect or Is the connector connected pump too high or low? DRAIN repair to pump motor assembly (resistance of the coil PUMP the connector. disconnected or is 10-20Ω) ASSEMBLY. disassembled? (Refer to 9-4 Pump motor assembly)
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HEATING ERROR Reconnect or Is the connector connected to repair thermistor disconnected or the connector disassembled? displayed? Reconnect or Is the connector connected repair to heater disconnected or the connector disassembled? Steam generator thermistor Dry thermistor Steam generator heater Wash thermistor Dry thermistor Replace the Is thermistor resistance...
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- part of motor LOCKED MOTOR ERROR displayed? Reconnect Check the connectors below. Motor the connector. Is the connector disconnected (connector / or disassembled? wire / motor) (motor hall sensor connector, Replace Is rotor magnet cracked? motor drive connector) the ROTOR - part of main PWB assembly (NA1, RD4) Magnet...
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DOOR OPEN ERROR Replace the Is there clicking sound once displayed? or twice when the ASSEMBLY. START/PAUSE button is pressed to start the cycle? Reconnect or Is the connector connected repair to door switch or main PWB Replace the Is DOOR SWITCH the connector disconnected? DOOR...
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UNBALANCE ERROR OVER FLOW ERROR displayed? displayed? When you press both Check the AIR Put laundry Does the laundry lean WASH/RINSE button and CHAMBER evenly toward one side, not evenly SOIL LEVEL button and the tube In the DRUM put in the DRUM assembly? simultaneously, is the (clogged).
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PRESSURE SENSOR ERROR displayed? Reconnect or Is the connector connected repair to pressure sensor the connector disconnected or disassembled? Replace the Is the resistance of the pressure pressure sensor out of switch range? (pin 1~ pin 3) (21~23 Ω ±10%) Fix the air Is the AIR CHAMBER and chamber...
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DRY HEATING ERROR Replace the Is the resistance values in the range of 2 to 5 Ω? FAN Motor Assembly (pin1-pin3, pin2-pin3) displayed? - After pull out the YL1 connector, check the terminal of the connector in wire.(Yellow 3P, male) Reconnect or Is the connector connected repair the...
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Replace the Is Check heater resistance Remove the After you separated Heater out of range while the power foreign condensing bellows from assembly is off? material cabinet, can you find any (10~40 Ω) foreign material in (Refer to 9-6 Heater condensing duct and assembly) condensing bellows?
8-5. TROUBLE SHOOTING ELSE CAUTION 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. NO POWER Replace the Is LED on while the power...
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BUTTON DOESN’T WORK Reconnect or Is the connector connected Repair to Main PWB / Display the connector PWB disconnected or disassembled? Replace the Is the display PCB broken? DISPLAY (check the buzzer sound and LED light while push ASSEMBLY the button.) Repair the Is the button of panel stuck? button...
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VIBRATION & NOISE IN SPIN Have all the transit bolts and base packing Remove the transit bolts been removed? and Base packing. Move the washer or Is the washer installed on a solidly constructed reinforce the floor. floor? Check if the washer is perfectly level as follows: Check the leveling of the washer with a level and check that the washer is stable.
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DETERGENT DOES NOT FLOW IN Refer to Is water supplied? NO WATER SUPPLY Are receptacles correctly connected to the Check the wiring. terminals of the INLET VALVE ASSEMBLY? Put the detergent in the correct place. Has detergent been put in the correct compartment of the dispenser? Is the detergent caked or hardened? Clean the dispenser.
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LIQUID DETERGENT/SOFTENER/BLEACH DOES NOT FLOW IN Refer to Is water supplied? NO WATER SUPPLY Check the wiring on the Are the plugs correctly connected to the terminals of dispenser. the INLET VALVE ASSEMBLY? Put it in the correct Is liquid detergent/softener/bleach put in the correct compartment.
9. COMPONENT TESTING INFORMATION WARNING When Resistance (Ohm) checking the Component, be sure to turn the power off, and do voltage discharge sufficiently. 9-1. FILTER ASSEMBLY (LINE FILTER) Wiring Circuit in the MAIN PWB / Wiring Diagram diagram RI CI MAIN PWB ASSEMBLY Test...
9-2. DOOR LOCK SWITCH ASSEMBLY Wiring Circuit in the MAIN PWB / Wiring Diagram diagram MAIN PWB MICOM Relay Relay Common terminal of Valve Door switch The Door Lock Switch Assembly consists of a Heating PTC, a Bimetal, a Function Protection PTC, and a Solenoid.
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Test points Result Test Points Result Remarks 700-1500 Ω (2) to (4) At 77 °F °C 60-90 Ω (3) to (4) At 77 °F °C (4) to (5) Infinity (2) to (4) 120 Vac Voltage Input Downloaded from www.Manualslib.com manuals search engine...
9-3. STATOR ASSEMBLY Wiring Circuit in the MAIN PWB / Wiring Diagram diagram MAIN PWB NA1NA MICOM Function The DD motor can be driven from stopped to maximum speed in infinite steps in either direction. There are 36 poles on the stator; 12 permanent magnets spaced around the rotor.
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The hall sensor determines the speed and direction of the motor. It also can read that the load is off balance when the drum speed fluctuates. Test point - Voltage Testing Hall Sensor at Stator Result (Hall Sensor) (2) (4) (1) (3) (5) If measuring voltage from the Main PCB Assembly to the Hall Sensor, use the following steps:...
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7. To measure output signal voltage from the hall sensor, carefully move test leads to terminals 1 to 4, blue and gray. Slowly rotate motor rotor by hand. You should read a pulsing 10 Vdc. If 10 Vdc is measured from 1 to 4, move lead on blue wire to red wire, terminal 2.
9-5. INLET VALVE ASSEMBLY Wiring Circuit in the MAIN PWB diagram MICOM CONNECTOR Inlet valve driving circuit INLET VALVE Wiring Diagram MIAN PWB COMMON GYOR BL (BK) MAIN BLEACH VALVE WASH VALVE WASH VALVE INLET VALVE * Each circuits of loads in wiring diagram are all same. Depending on the cycle and water temperature, the controller will energize the hot or Function cold water valve solenoids to meet the selected water temperature.
9-6. HEATER ASSEMBLY Wiring Circuit in the MAIN PWB Wiring diagram diagram MAIN PWB MICOM Heater Tab Relay STEAM WASH Heater driving circuit HEATER GENERATOR HEATER HEATER * Each circuits of loads in wiring diagram are all same. 1. The Wash Heater is designed to raise the wash water to the desired temperature Function selection during certain wash cycles.
9-7. THERMISTOR ASSEMBLY Wiring Circuit in the MAIN PWB / Wiring Diagram diagram MAIN PWB MICOM Wash THERMISTOR The thermistor (temperature sensor) is used to monitor water temperature in the Function tub, Steam Generator, Dry duct and Condensing duct. Test points (1) (2) Wash Thermistor...
Result Wash Thermistor / Dry Thermistor Test Points Result Remarks (tolerance ±5%) (1) to (2) 39.5 kΩ At 86°F (30°C) 26.1 kΩ At 104°F (40°C) (2) to (3) At 140°F (60°C) 12.1 kΩ At 158°F (70°C) 8.5 kΩ At 203°F (95°C) 3.8 kΩ...
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9-8. STEAM GENERATOR ASSEMBLY Wiring Steam generator Water level sensor diagram circuit in the MAIN PWB / wiring diagram MAIN PWB DC5V IC 2 IC 1 Input A PHOTO (long) COUPLER MICOM Input B (short) GND L SENSOR Heater & Thermistor : Refer to the 9-6 / 9-7 Original THERMISTOR HEATER...
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2) Operation mechanism of Steam generator Function After supplying some amount of water through inlet valve and water level sensor, Heater operates and steam generates. Generated steam is sprayed by nozzle. If the water in the steam generator is reduced by spraying steam, water level sensor decide to supply water or not.
9-9. LAMP Wiring Circuit in the MAIN PWB / Wiring Diagram diagram 16.5V MAIN PWB MICOM 1 2 3 1 2 3 Function The Lamp (Drum Light) comes on when the POWER button is pressed. It goes off when the door is closed and the washer starts operation. It remains off when the door is locked.
10. DISASSEMBLY INSTRUCTIONS CONTROL PANEL ASSEMBLY Downloaded from www.Manualslib.com manuals search engine...
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MAIN PWB ASSEMBLY Disconnect the POWER connector and SENSOR SWITCH ASSEMBLY. Remove the Protective cover. Disconnect the connectors. Unscrew 1 screw on the back. Remove the Main PWB. Downloaded from www.Manualslib.com manuals search engine...
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DISPENSER ASSEMBLY Disassemble the top plate assembly. Pull out the drawer. Push out the DISPENSER ASSEMBLY after unscrewing 2 screws. Unscrew the Clamp nut at the lower part of the dispenser. Disassemble the 4 connectors from the valves. Wire Color Blue Housing (YL-BK) Red Housing (VT-BK) White Housing (WH-BK)
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CABINET COVER Unscrew the 5 screws from upper of the canbinet cover. Unscrew the screw from filter cover. Put a flat ( -) screwdriver or putty knife into the hinge slots at the bottom of the cover and pry it out. Unscrew the screw from the lower side of the cabinet cover.
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Open the door. Disassemble the clamp assembly. Tilt the cabinet cover. Disconnect the door switch connector. NOTE: When assembling the CABINET COVER, connect the door switch connector. Lift and separate the cabinet cover. Disassemble the clamp assembly. Disassemble the gasket. Downloaded from www.Manualslib.com manuals search engine...
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DOOR ① ① Open the door. ② ② Unscrew the 7 screws from the HINGE COVER. ③ ③ Put a flat ( - ) screwdriver into the openng of the hinge, and pull out the hinge cover. ④ ④ Unscrew a screw from the lower side of door. ⑤...
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PUMP ① ① Disassemble the cabinet cover. ② ② Separate the pump hose, the bellows and the circulation hose assembly from the pump assembly. ③ ③ Disassemble the pump assembly in arrow direction. HEATER ① ① Disassemble the cabinet cover. ②...
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WHEN FOREIGN OBJECT IS STUCK BETWEEN DRUM AND TUB ① ① Disassemble the cabinet cover. ② ② Separate the heater from the tub. ③ ③ Remove any foreign objects (wire, coin, etc.) by inserting a long bar in the opening. LAMP ASSEMBLY TOP PLATE ASSEMBLY ①...
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MOTOR/DAMPER Disassemble the back cover. Remove the bolt. Pull out the Rotor. Unscrew the 2 screws from the tub bracket. Remove the 6 bolts on the stator. Unplug the 2 connectors from the stator. Disassemble the damper hinges from the tub and base.
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Checking the TSG (TURBO STEAM GENERATOR) To check out the fault diagnosis of TSG, you can pull out the plug and let the water drain away. Be cautious in case of the TSG is hot. TSG (TURBO STEAM GENERATOR) Remove the housing attached to the TSG (Heater, Water level frequency-sensor, Thermistor) Remove the screw of the TSG and Body...
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Taking out the screws of Body Frame (2 ea) Separate the hoses from the TSG. Remove the body frame and then, separate the TSG from the washer Downloaded from www.Manualslib.com manuals search engine...