Website:http://biz.lgservice.com WASHING MACHINE SERVICE MANUAL CAUTION READ THIS MANUAL CAREFULLY TO DIAGNOSE PROBLEMS CORRECTLY BEFORE SERVICING THE UNIT. MODEL : WM3987H*...
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NOV. 2009 PRINTED IN KOREA P/No.: MFL30138960...
1. SPECIFICATIONS ITEM WM3987H* COLOR BLUE WHITE POWER SUPPLY AC 120 V, 60 Hz PRODUCT WEIGHT 201 lbs (91kg) WASHING 280 W ELECTRIC DRAIN MOTOR 80 W POWER CONSUMTION 1000 W WASH HEATER 46 rpm WASH REVOLUTION SPEED SPIN 0 - 1200 rpm CYCLES WASH/RINSE TEMPERATURES SPIN SPEEDS...
2. FEATURES & TECHNICAL EXPLANATION 2-1. FEATURES Direct Drive System The advanced Brushless DC motor directly drives the drum without belt and pulley. Tilted Drum and Extra Large Door Opening The tilted drum and extra large door opening make it possible to load and unload easily.
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...
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..). 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. Avoid submerging the end of the hose. The end of the drain hose should be placed less than 100 cm from the floor.
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.
6. OPERATION Power Button Status Indicator • Use this button to turn the power • It shows elapsed time of the cycle the washer On/Off. is operating. C C O O T T T T O O N N / / N N O O R R M M A A L L B B U U L L K K Y Y / / L L A A R R G G E E P P R R E E M M .
Option Button • PREWASH : Use this option for loads that need pretreatment. It adds 16 minutes prewash and a spin cycle. • EXTRA RINSE: This option provides an additional rinse. • STAIN CYCLE: Adds time to the wash and rinse cycles for better stain removal. Automatically provides a rinse.
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. The washer must be empty and the controls must be in the off state. 1.
7-4. 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.
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ERROR SYMPTOM CAUSE OVER • MAIN PWB ASSEMBLY is out of order. CURRENT • Winding in the STATOR ASSEMBLY is short-circuited. ERROR • The connector (3-pin, male, white) in the MOTOR HARNESS is not connected to the connector (3-pin, female, white) of STATOR ASSEMBLY. •...
8. ERROR DIAGNOSIS AND CHECK LIST 8-1. DIAGNOSIS AND SOLUTION FOR ABNORMAL OPERATION SYMPTOM GUIDE FOR SERVICE CALL No power Is the power plug connected firmly to 120V AC outlet? Power failure? or Breaker opened? Is the outlet controlled by a switch? Visit to service.
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SYMPTOM GUIDE FOR SERVICE CALL Door error Was the load too large? Visit to service. Drain trouble Visit to service.
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SYMPTOM GUIDE FOR SERVICE CALL Suds overflow from the Is a low-sudsing detergent used? appliance. (In this condition, wash and spin do not operate normally) LOW-SUDSING Is the proper amount of detergent used as recommended? Recommend to reduce the amount of detergent.
8-2. FAULT DIAGNOSIS AND TROUBLESHOOTING 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 Check the fuse or reset Is the supplied voltage 120V AC?
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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. Is the washer installed on a solidly constructed Move the washer or floor? reinforce the 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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If it still has severe vibration and noise, regulate a specific spin speed that generates excessive vibration and noise as follows: 1) Put an unbalance part (rubber) inside of the drum. 2) Start the QC test mode (Refer to section 7-2). 3) Press Delay Wash button, then ‘...
NO WATER SUPPLY Is water supply shut-off? Is the tap opened? Open the tap. When you press both SPIN button and RINSE Check the AIR CHAMBER button simultaneously, is the water level frequency and the tube (clogged). below 246? Is the inlet valve filter clogged? Clean the filter.
LIQUID DETERGENT/SOFTENER 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.
HEATING WITHOUT WATER When pressing WASH/RINSE and SOIL LEVEL at the same time after draining, is the water level Replace the frequency 255? SENSOR SWITCH When pressing WASH/RINSE and SOIL LEVEL ASSEMBLY. buttons at the same time while washing, is the water level frequency between 230 - 243 ? Check the voltage between two pins while pressing Replace the MAIN PWB...
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WASH HEATER TROUBLE When checking the voltage between connector during whites washing. Is the voltage 120 V AC? HEATING CONTINUOUSLY ABOVE THE SETTING WATER TEMPERATURE Push the THERMISTOR When checking the THERMISTOR on the tub, tightly to the rubber. is the THERMISTOR loose?
WILL NOT CIRCULATE WATER Is the impeller of the drain pump clogged? Remove foreign material. Remove foreign material. Are the Hose Connector and/or Hose clogged? Reconnect or repair Is the connector disconnected, disassembled? the connector. Is the coil of the right side of drain pump open Replace PUMP MOTOR or short circuited? (Coil R is 18-30 Ω) ASSEMBLY.
SPIN TROUBLE Check the SENSOR SWITCH Check during spin if the frequency of the water ASSEMBLY or HOSE (Pressure). level is 248 or more. If the problem is on the SENSOR SWITCH ASSEMBLY or the HOSE, replace the SENSOR SWITCH ASSEMBLY or the HOSE.
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Replace the thermistor. Is the resistance of thermistors on dry duct 6322FR2046C : Dry 2.5kΩ - 180kΩ (at 100 Duct Disassemble the cabinet cover and condensing bellows. Clean the bellows Is there any foreign object in the condensing bellows. Disassemble the dry fan assembly and dry duct upper, and remove foreign objects in duct and fan.
9. DISASSEMBLY INSTRUCTIONS Be sure to unplug the machine out of the outlet before disassembling and repairing the parts. Unscrew 2 screws on the back of the top plate. Unscrew 2 screws on the back of the top plate. Pull the top plate backward and upward as shown. Pull the top plate backward and upward as shown.
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Disconnect the POWER connector and SENSOR SWITCH ASSEMBLY. Remove the Protect Cover. Disconnect the connectors. Unscrew 1 screw on the back. Disassemble the Main PWB.
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Disassemble the top plate assembly. Pull out the drawer. Push out the DISPENSER ASSEMBLY after unscrew 2 screws. Unscrew the 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) Blue Housing(GY-BK)
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Unscrew the a screw from the Top Bracket. Disassembly one connector from the Main PWB. Unscrew the 4 screws from upper of the canbinet cover. Unscrew the screw from filter cover. Put a flat ( - ) screwdriver or putty knife into the both sides of the filter cover, and pull it out.
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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 connector. Lift and separate the cabinet cover. Disassemble the clamp assembly. Disassemble the Gasket.
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Open the door. Unscrew the 7 screws from the HINGE COVER. Put a flat ( - ) screwdriver into the openng of the hinge, and pull out the hinge cover. Unscrew a screw from the lower side of door. Disassemble the door upward. Be careful! The door is heavy.
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Disassemble the cabinet cover. Separate the pump hose, the bellows and the circulation hose assembly from the pump assembly. Disassemble the pump assembly in arrow direction. Disassemble the cabinet cover. Separate 2 connectors from the heater. Loosen the nut and pull out the heater. CAUTION •...
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Disassemble the cabinet cover. Separate the heater from the tub. Remove any foreign objects (wire, coin, etc.) by inserting a long bar in the opening. Unscrew the 4 screws from the back cover. Unscrew the single screw from the lower-right side of the cabinet.
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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.