LG LMVM2033BM, Service Manual

Page 1: ...ROWAVE OVEN SERVICE MANUAL MODEL LMVM2033SW LMVM2033SB LMVM2033ST CAUTION BEFORE SERVICING THE UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL P NO MFL06272535 June 2014 Printed in Korea Internal Use Only ...

Page 2: ... proper alignment integrity and connections d Any defective or misadjusted components in the interlock monitor door seal and microwave generation and transmission systems shall be repaired replaced or adjusted by procedures described in this manual before the oven is released to the owner e A microwave leakage check to verify compliance with the federal performance standard should be performed on ...

Page 3: ...anation of Control Panel 8 5 Wiring Diagram Key Matrix 9 5 1 Wiring Diagram 9 5 2 Key Matrix 10 6 Troubleshooting 11 6 1 General Information for Service 11 6 2 Safety Caution 12 6 3 Self diagnosis humidity Sensor and PCB thermistor check Error code 12 6 4 Basic Check Summary 13 6 5 Troubleshooting 14 7 Microwave Leakage Test 24 8 Power Output Measurement 26 9 Interlock System 27 9 1 Interlock Mech...

Page 4: ...agnetron 2M246 050GP Cook Top Lamp Halogen lamp 130V 50W Cavity Lamp 125 V 30 W or 40 W Timer Digital up to 99 min 99 sec in each cooking stage Tray Tempered Safety Glass Overall Dimensions 2914 16 W x 16 7 16 H x 15 13 16 D Oven Cavity Size 22 W x 115 8 H x 14 5 8 D Effective Capacity of Oven Cavity 2 0Cu ft Accessories Ownerʼs Manual Cooking Guide Installation Manual Exhaust Adapter Exhaust Damp...

Page 5: ...ng operation BEFORE TOUCHING any parts of the oven always remove the power plug from the outlet Remove your watches whenever working close to or replacing the magnetron DO NOT touch any parts of the control panel circuit A resulting static electric discharge may damage the P C B NEVER operate the oven with no load NEVER injure the door seal and front plate of the oven cavity NEVER put iron tools o...

Page 6: ...dio etc to prevent interference GROUNDING INSTRUCTIONS For personal safety this appliance must be fully grounded at all times In the event of an electrical short circuit grounding reduces the risk of electric shock The plug must be plugged into an outlet that is properly installed and grounded CAUTION This unit is equipped with a 3 prong plug for your safety If the wall outlet is a grounded 3 hole...

Page 7: ... 7 4 Operation 4 1 Control Panel 9 10 11 12 13 14 8 7 6 5 4 3 2 1 21 22 23 24 25 15 16 17 18 19 20 ...

Page 8: ...el quantities or weights 11 Touch this button to add or subtract ten seconds of cooking time each time you touch it 12 ADD 30 SEC Press this button to control the add 30sec cook time 13 START ENTER Press this button to start a function If you open the door after oven begins to cook press START ENTER again 14 Light High Low Off touch this button to turn the cooktop coutertop light on high low or of...

Page 9: ...VL VIOLET ORANGE YL PK PK GY BL RD WH BK C L RD BN YL YL 21VAC CAPACITOR PK WH BN GY WH RD WH RD BN YL 180 60 356 140 WH WH YL PK YL W O L H G I H O B R U T VL 1 2 3 4 5 6 7 8 SLOW WH OG YL BL 7 10 RD BN BK BL 1 2 3 4 5 6 7 8 WH WH 8 3 H W WH H W H V FUSE ...

Page 10: ...k Hold Warm C T Lamp On Off Start 13 More Sensor Cook time weight Defrost N A N A N A N A SensorPopcorn 12 Less Sensor Reheat Timer 0 9 8 7 11 Melt 6 5 4 3 2 1 10 Soften Quick Defrost Add 30 Sec Energy Saving Clock Vent Hi Low Off Clear 9 8 7 6 5 4 3 2 1 2st KEY MATRIX ...

Page 11: ...ay window will show the time counting down by seconds D After about 5 minutes make sure the primary interlock switch the secondary interlock switch and the interlock monitor switch operate properly by opening and closing the door several times Press the START button each time the door is closed E Continue operating the unit Two short beeps and one long beep will sound when the time is up The unit ...

Page 12: ...rmly b The hinge is broken c The door seal is damaged d The door is bent or warped or there is any other visible damage on the unit that may cause microwave energy leakage NOTE Always keep the seal clean e Make sure that there are no defective parts in the interlock mechanism f Make sure that there are no detective parts in the microwave generating and transmission assembly especially waveguide 4 ...

Page 13: ...H H W H V FUSE Symptom Dead Check Open Short Symptom 1 Door is closed Not cooking Not operating V M T T M Check Open Short when the door is closed Switch Symptom 2 Door is open Operating V M T T M automatically Check Open Short when the door is open Switch Symptom 1 Door is closed No key Not started Operating O L V M T T M Check Open Short when the door is closed Switch Symptom 2 Door is open Not ...

Page 14: ...play Check connection OG VL VIOLET ORANGE YL PK PK GY BL RD WH BK C L RD BN YL YL 21VAC CAPACITOR PK WH BN GY WH RD WH RD BN YL 180 60 356 140 WH WH YL PK YL W O L H G I H O B R U T VL 1 2 3 4 5 6 7 8 SLOW WH OG YL BL 7 10 RD BN BK BL 1 2 3 4 5 6 7 8 WH WH 8 3 H W WH H W H V FUSE No Display or Dead ...

Page 15: ...n the continuity test between the power cord and the connector Code L to Pin1 Code N to Pin3 No Yes Check PCB Go to No 6 of this flow chart Go to No 6 of this flow chart Is there any beeping sound in the continuity test between the ends of the fuse Yes No Replace the Fuse L L L L L L L L L L L L L L L L L L L L L L N N N N N N N N N N N N N N N N N N N N N N Is there any beeping sound in the conti...

Page 16: ... 16 Keypad Failure ...

Page 17: ... Door should be closed Power ON Yes No Adjust latch board Refer to section 9 1 9 2 Check PWB Go to No 4 of this flow chart 3 When the door is opened is the voltage of the door sensing part over 4 V CN3 Pin1 and Pin2 Yes No Replace the PCB EBR75341201 Reconnect or repair the connector Replace the PCB EBR75341201 4 Is the connector connected to the PCB disconnected or disassembled No Yes Replace the...

Page 18: ... RD WH BK C L RD BN YL YL 21VAC CAPACITOR PK WH BN GY WH RD WH RD BN YL 180 60 356 140 WH WH YL PK YL W O L H G I H O B R U T VL 1 2 3 4 5 6 7 8 SLOW WH OG YL BL 7 10 RD BN BK BL 1 2 3 4 5 6 7 8 WH WH 8 3 H W WH H W H V FUSE No Heat No Cook ...

Page 19: ...and TAB2 No Yes PCB no problem Alternate explanation refer to the Note 3 While the product is operating under EZ ON start is the voltage of both ends of the D35 over 8 V No Yes Replace the Relay 2 4 Replace the PCB EBR75341201 Note If something is caught in the door or in the sealing area the microwave oven cannot operate safely The latch switches and monitor switch will prevent operation ...

Page 20: ...rd Refer to section 9 1 9 2 Is the resistance of the high voltage Transformer out of range Test Point 1 Primary winding 0 2 0 5 Ohm 2 Secondary 50 120 Ohm 3 Filament winding 0 Ohm No Yes Replace the High Voltage Transformer Is the connector connected to High Voltage Transformer assembly disconnected or disassembled No Yes Reconnect or repair the connector ...

Page 21: ...ltage diode assembly disconnected or disassembled No Yes Reconnect or repair the connector Forward Forward Forward Forward Forward Forward Forward Forward Forward Forward Forward Forward Forward Forward Forward Forward Forward Forward Forward Forward Forward Forward Case ground Case ground Is the connector connected to the magnetron assembly disconnected or disassembled Yes Forward Forward Forward...

Page 22: ... to section 9 1 9 2 Replace the turntable motor Power ON 3 Push the EZ ON button operate Is the voltage of both ends of the D37 over 8 V Yes No Replace the PCB EBR75341201 4 Is there any beeping sound in the continuity test between the ends of two Pin of RY1 Yes No Replace the PCB EBR75341201 5 PCB No Problem Turntable Motor Does Not Work ...

Page 23: ... the continuity test between the ends of the latch board Secondary switch Door should be closed Yes No Adjust latch board refer to section 9 1 9 2 Power ON 4 When the door is opened Is the voltage of the door sensing part over 4 V Pin 11 to Pin 12 Yes No Replace the PCB EBR75341201 4 Is there any beeping sound in the continuity test between the ends of the two pins of RY1 No Yes Is the voltage of ...

Page 24: ...adiation leakage emitted by the microwave oven should not exceed 1 mW cm2 sq Always start measuring of an unknown field to assure safety for operating personnel from radiation leakage NOTE The standard is 5 mW cm2 sq while in the customerʼs home 1 mW cm2 sq stated here is manufacturerʼs own voluntary standard for units in customerʼs home EQUIPMENT TESTER VOLTS DC AC Ohmmeter Microwave survey meter...

Page 25: ...eter full scale deflection 2 The test probe must be removed no faster than 1 inch sec 2 5 cm sec along the shaded area otherwise a false reading may result 3 The test probe must be held with the grip portion of the handle A false reading may result if the operator ʼs hand is between the handle and the probe 4 When testing near a corner of the door keep the probe perpendicular to the surface making...

Page 26: ...10 1 K is measured where t is the time in seconds and T is the temperature rise The initial and final water temperatures are selected so that the maximum difference between the final water temperature and the ambient temperature is 5 K 6 The microwave power output P in watts is calculated from the following formula 4 187 Mw T2 T1 0 55Mc T2 T0 t is measured while the microwave generator is operatin...

Page 27: ...removed 1 Set the microwave oven on its side so that you can see the latch board and the switches as shown inFigure 23 a 2 Close the door tightly and check gaps A and B to be sure they are no more than 1 64 0 5 mm See Figure 23 b for close up view of gaps A and B door latches If all gaps are less than 1 64 0 5 mm adjustment of the latch board may not be necessary Go to Steps 5 and 6 to check the s...

Page 28: ... zero to the body of the switches in the following sequence Interlock Monitor Switch Primary Interlock Switch Secondary Interlock Switch NOTE The Interlock Monitor Switch is an added safety check on the Primary and Secondary Interlock Switches If the Primary and Secondary Interlock Switches allow the oven to operate with the door open the Monitor Switch will blow the fuse 7 When you achieve the pr...

Page 29: ...ssary adjustment or replace the switch making sure to replace it with the same type of switch C MONITOR SWITCH TEST Disconnect the wire lead from the monitor switch Connect the ohmmeter leads to the common COM and normally closed NC terminals of the switch The meter should indicate a closed circuit in the door open condition If the door is closed the meter should indicate an open circuit If the mo...

Page 30: ... wire leads 2 Measure resistance ohm meter scale Rx1 Primary winding Secondary winding Filament winding 3 Measure resistance ohm meter scale Rx1000 Primary winding to ground Filament winding to ground 1 Remove wire leads Install the magnetron seal in the correct position Check that the seal is in good condition 2 Measure resistance ohm meter scale Rx1 Filament terminal 3 Measure resistance ohm met...

Page 31: ...ance in both directions 1 Measure continuity ohm meter scale Rx1 2 Remove the lead wires and operate oven at power level 1 through power level 10 Relay 2 1 Remove lead wires 2 Measure resistance ohm meter scale Rx1 Turbo speed White and Brown High speed White and Blue Low speed White and Violet Slow speed white and Yellow Normal Turbo speed Approximately 20 25ohms High speed Approximately 40 45ohm...

Page 32: ...2 resistor 1 5M ohms Abnormal 0 ohms Normal under 10ohm Abnormal infinite 1 Remove wire leads 2 Measure resistance ohm meter scale Rx1000 1 Unplug microwave oven or disconnect power 2 Remove wire 3 Measure resistance ohmmeter scale Rx1 test 1 Depart from other components 2 Measure Resistance ohm meter scale Rx1 L 1 L 2 N 2 N 1 Turntable Motor NOISE FILTER HIGH VOLTAGE FUSE L 1 L 2 N 2 N 1 L 1 L 2 ...

Page 33: ...ore than 1 megaohm FPC CONNECTOR Top NOTES A MICROWAVE ENERGY TEST MUST ALWAYS BE PERFORMED WHEN THE UNIT IS SERVICED FOR ANY REASON MAKE SURE THE WIRE LEADS ARE IN THE CORRECT POSITION WHEN REMOVING THE WIRE LEADS FROM THE PARTS BE SURE TO GRASP THE CONNECTOR NOT THE WIRES KEY MATRIX Turntable On Off Power Level Time Cook Hold Warm C T Lamp On Off Start 13 More Sensor Cook time weight Defrost N A...

Page 34: ...1 2 and 3 1 Remove the a screw securing the control panel assembly to the oven cavity 2 Remove the control panel by pushing it upward 3 Remove the connectors cn1 cn3 cn5 and wire leads RY1 RY2 from the circuit board 4 Remove 5 screws securing the circuit board 5 Remove the FPC connector from the terminal socket following HOW TO REMOVE THE FPC CONNECTOR on the next page 6 Remove the circuit board f...

Page 35: ... by loosening the screws 1 or 2 screws securing it to the outer case 4 Remove two screws on the left central edge and one screw on the right central edge of the base plate Remove the fan bracket from the outer case by removing one screw securing it to the outer case 5 Remove six screws of the rear cavity 6 Remove the outer case Fan Bracket Door Outer Case Vent Grill Control Panel Power Cord Figure...

Page 36: ...BLACK BR BROWN RD RED YL YELLOW PK PINK BL BLUE GY GREY GN GREEN N P Not Provided C REMOVING THE DOOR INTERLOCK SWITCHES Figures 9 10 1 Disconnect the wire leads from the interlock switches 2 Remove the two screws securing the Latch Board 3 Make any necessary replacements and check for microwave energy leakage according to ADJUSTMENT PROCEDURES on page 7 12 ...

Page 37: ...g the magnetron make sure that its dome does not hit any adjacent parts or it may be damaged When replacing the magnetron be sure to install the magnetron gasket in the correct position and be sure that the gasket is in good condition After replacing the magnetron check for microwave energy leakage with a survey meter Checked microwave energy leakage must be below the limit of 5 mW cm2 All service...

Page 38: ...ve the two screws securing it to the door handle CAUTION Be careful not to damage the door seal plate with the screwdriver H ASSEMBLING DOOR 1 When mounting the door assembly to the oven assembly be sure to adjust the door assembly parallel to the chassis Also adjust it so the door has no play between the inner door surface and oven frame assembly If the door assembly is not mounted properly micro...

Page 39: ... by removing the 8 screwssecuring it to the oven cavity Figure 19 4 Disconnect the lead wire from the turntable motorterminals 5 Remove the 1 screw securing the turntable motorto the oven cavity assembly Figure 20 NOTES Remove the lead wire from the turntable motor VERY CAREFULLY Be sure to grasp the connector not the wires when removing Figure 18 Figure 19 Figure 20 ...

Page 40: ... Exploded View INTRODUCTION OVEN CAVITY PARTS INTERIOR PARTS LATCH BOARD PARTS CONTROL PANEL PARTS DOOR PARTS EV MODELS Customer Model Product Code SVC Model ...

Page 41: ...DOOR PARTS 1004 1002 1000 1005 1009 1007 1006 1381 W262 1034 EV MODELS Customer Model Product Code SVC Model ...

Page 42: ...2004 2381 W262 2008 2006 EV CONTROLLER PARTS MODELS Customer Model Product Code SVC Model ...

Page 43: ...OVEN CAVITY PARTS 6000 3025 3026 3026 3011 3028 3010 3001 3034 3036 303R 3018 3036 303L 3024 3029 3029 3005 EV ...

Page 44: ...W102 4000 4001 4004 4002 4003 4002 LATCH BOARD PARTS EV ...

Page 45: ...INTERIOR PARTS I EV 3037 3009 5014 3002 3012 5016 5030 5002 5000 5116 5023 5009 5049 W101 W101 W101 5008 5034 5022 5018 3008 5019 ...

Page 46: ...INTERIOR PARTS II EV 5010 5012 5073 5007 W265 5412 5103 5004 5037 5102 5068 W140 W140 W140 5001 5006 5069 5041 3027 5206 5038 5074 5015 5011 5058 W248 5044 5043 3004 5024 5075 W140 ...

Page 47: ...6011 6010 6009 6008 VINYL BAG MBM5 MBM4 INSTALLATION PARTS EV ...

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