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IMPORTANT NOTES:

UNIT MUST BE DISCONNECTED FROM
ELECTRICAL OUTLET WHEN MAKING REPAIRS,
RE-PLACEMENTS, ADJUSTMENTS AND CONTIN-
UITY CHECKS. WAIT AT LEAST ONE MINUTE,
UNTIL THE HIGH VOLTAGE CAPACITOR IN THE
HIGH VOLTAGE POWER SUPPLY HAS FULLY
DISCHARGED.
THE CAPACITOR SHOULD BE DISCHARGED BY
USING INSULATED WIRE - I.E. TEST PROBE
CONNECTED TO 10K-OHM RESISTOR IN SERIES
TO GROUND. 
WHEN RECONNECTING THE WIRE LEADS TO
ANY PART, MAKE SURE THE WIRING CONNE-
CTIONS AND LEAD COLORS ARE CORRECTLY
MATCHED ACCORDING TO THE OVERALL CIR-
CUIT DIAGRAM. (ESPECIALLY SWITCHES AND
HIGH VOLTAGE CIRCUIT.)

A.  REMOVING POWER AND CONTROL

CIRCUIT BOARD (Figures 1, 2 and 3)

(1) Remove a screw securing the control panel

assembly to the oven cavity.

(2) Remove the control panel with pushing it upward. 
(3) Remove the connector (CN1) and wire leads

(Relay6) from the circuit board.

(4) Remove 2 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 from the control bracket 

carefully.

 Circuit Board

Figure 2

Figure 3

Control Bracket

FPC Connector(S1)

 Circuit Board

DISASSEMBLY INSTRUCTIONS

Figure 1

Screw

 Control Panel

(Relay 7)

Relay 7

Power Transformer

(CN1)

7-4

Summary of Contents for MV1615W

Page 1: ...MICROWAVE OVEN SERVICE MANUAL MODEL MV1615W CAUTION BEFORE SERVICING THE UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL website http www lgservice com ...

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 CSA Standard should be performed on each oven prior ...

Page 3: ...RAM 5 1 MATRIX CIRCUIT FOR TOUCH KEY BOARD 5 2 GENERAL INFORMATION FOR SERVICE 6 1 GENERAL PRECAUTIONS IN USE 6 1 TRIAL OPERATION 6 1 FEATURES AND SPECIFICATIONS FEATURES 6 1 SERVICE INFORMATION 7 1 PRECAUTIONS AND REPAIR SERVICE TIPS 7 1 MICROWAVE LEAKAGE TEST 7 2 POWER OUTPUT MEASUREMENT 7 3 DISASSEMBLY INSTRUCTIONS 7 4 INTERLOCK SYSTEM 7 12 INTERLOCK CONTINUITY TEST 7 14 TEST AND CHECKOUT PROCE...

Page 4: ...vity Thermostat Open at 90 C 5 C Fuse 20A Primary Interlock Switch Secondary Interlock Switch Interlock Monitor Magnetron 2M214 39F High Voltage Capacitor Capacitor 1 0µF 2 1 KV AC High Voltage Diode Diode 350mA 9 0 KV Cook top Lamp 125 V 30 W Cavity Lamp 125 V 30 W Timer Digital up to 99 mim 99 sec in each cooking stage Tray Tempered Safety Glass Overall Dimensions 29 15 16 W x16 7 16 D x15 3 8 H...

Page 5: ... area Proper operation of the microwave oven requires that the magnetron be assembled to the waveguide and cavity Never operate the magnetron unless it is properly installed Be sure that the magnetron gasket is properly installed around the dome of the tube whenever installing the magnetron Unlike other appliances the microwave oven is high voltage and high current equipment Though it is free from...

Page 6: ...d at all times In the event of an electrical short circuit grounding reduces the risk of electrical shock The plug must be plugged into an outlet that is properly installed and grounded BEFORE YOU BEGIN READ THE FOLLOWING INSTRUCTIONS COMPLETELY AND CAREFULLY WARNING Improper use of the grounding plug can result in a risk of electric shock Do not under any circumstances cut or remove the third gro...

Page 7: ...4 1 OPERATING INSTRUCTIONS CONTROL PANEL 4 7 10 14 15 16 19 9 21 24 26 23 1 5 8 17 20 22 25 18 11 13 6 3 2 12 ...

Page 8: ...ch this pad to set and start quickly at 100 power level 13 NUMBER Touch number pads to enter cooking time power level quantities or weights 14 CUSTOM SET Touch this pad to change the oven s default settings for sound clock display speed and defrost weight 15 CLOCK Touch this pad to enter the time of day 16 HOLD WARM Touch this pad to keep hot cooked foods safety warm in your microwave oven for up ...

Page 9: ...5 1 OVERALL CIRCUIT DIAGRAM SCHEMATIC DIAGRAM ...

Page 10: ...K FAN HI LO OFF HELP COOK POPCORN AUTO DEFROST LIGHT HI LO OFF CUSTOM SET REHEAT POTATO KITCHEN TIMER CLOCK LESS Ez On BEVERAGE POWER LEVEL CUSTOM COOK LIGHT TIMER N C PIZZA HOLD WARM T TABLE ON OFF STOP CLEAR START N C N C N C MORE N C N C N C N C ...

Page 11: ...TART key Make sure the cavity light comes on The unit will begin cooking and the display 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 Touch the START key each time the door is closed E Continue operating ...

Page 12: ... microwave energy leakage must bebelow the limit of 5 mW cm2 All service adjustments should be made for minimum microwave energy leakage readings 3 Do not operate the unit until it is completely repaired if any of the following conditions exist The unit must not be operated a The door does not close firmly b The hinge is broken c The door seal is damaged d The door is bent or warped or there is an...

Page 13: ...he microwave oven should not exceed 4 mW cm2 Always start measuring of an unknown field to assure safety for operating personnel from radiation leakage EQUIPMENT TESTER VOLTS DC AC Ohmmeter Microwave survey meter Holaday HI 1500 HI 1501 Narda 8100 8200 600 cc non conductive material beaker glass or plastic inside diameter approx 8 5 cm 31 2 in Glass thermometer 100 C or 212 F 1 deg scale MEASURING...

Page 14: ...leakage before the outer case is installed and after all necessary components are replaced or adjusted Special care should be taken in measuring the following parts Around the magnetron The waveguide WARNING AVOID CONTACTING ANY HIGH VOLTAGE PARTS MEASUREMENT WITH A FULLY ASSEMBLED OVEN 1 After all components including the outer panels are fully assembled measure for microwave energy leakage aroun...

Page 15: ...L CIR CUIT DIAGRAM ESPECIALLY SWITCHES AND HIGH VOLTAGE CIRCUIT A REMOVING POWER AND CONTROL CIRCUIT BOARD Figures 1 2 and 3 1 Remove a screw securing the control panel assembly to the oven cavity 2 Remove the control panel with pushing it upward 3 Remove the connector CN1 and wire leads Relay6 from the circuit board 4 Remove 2 screws securing the circuit board 5 Remove the FPC connector from the ...

Page 16: ...he F P C connector into the terminal socket securely with the fingers 2 Hold the plastic fastener with thumb and forefinger of the other hand and push it slowly into the terminal socket Figure 6 NOTE When reconnecting the F P C connector make sure that the holes on the F P C connector are properly engaged with the hooks on the plastic fastener 3 Lock the level of the plastic fastener into the hook...

Page 17: ...ove the base plate by removing six screws securing it to the out case Remove the Mount All from the out case by removing two screws securing it to the out case and one screw securing it to the ventilation motor ASS Y and cavity 6 Remove the power cord cover from outcase by removing a screw 7 Remove the power cord to the inner of the out case with turning power cord and remove the out case with pus...

Page 18: ... 7 12 Latch Board WH from H V Transformer WH from Monitor S W WH from Oven Thermostat WH from Cooktop lamp Secondary Interlock Switch Monitor Interlock Switch Primary Interlock Switch GN from P C B YL from P C B WH from Secondary switch RD from Ry 7 Figure 9 Latch Board Secondary Interlock Switch Interlock Monitor Switch Primary Interlock Switch Figure 10 WIRE COLOR SYMBOL COLOR WH BK BR RD BL PK ...

Page 19: ...s 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 Check microwave energy leakage must be below the limit of 5 mW cm2 All service adjustments should be made for minimum microwave energy leakage reading...

Page 20: ...erlock switch and the interlock monitor switch is in good operating normally After replacing the door check for microwave energy leakage with a survey meter Microwave energy leakage must be below the limit of 5mW cm2 With a 275 ml water load G DISASSEMBLING DOOR Figure 15 1 Remove the dielectric choke by using knife blade or small screw driver etc 2 Remove two screws securing it to the door handle...

Page 21: ...ted properly microwaves may leak from the clearance between the door and the oven I REMOVING THE VENTILATION FANASS Y 1 Remove the mounting plate by removing two screws securing it to the back plate See Figure 16 2 Remove the two screws securing the MOUNT ALL and one screw securing the ventilation fan ASS Y See Figure 17 3 Carefully pull the ventilation motor ASS Y out of the microwave oven See Fi...

Page 22: ...ews securing it to the oven cavity Figure 20 4 Disconnect the leadwire from the turntable motor terminals 5 Remove the 2 screws securing the turntable motor to the oven cavity ASS Y Figure 21 NOTES Remove the leadwire from the turntable motor VERY CAREFULLY Be sure to grasp the connector not the wires when removing Wire Leads Turntable Motor Figure 21 Figure 19 Figure 20 7 11 ...

Page 23: ...holding the plastic latch board as shown 4 With the oven door closed tightly move the latch board upward toward the top of the oven and or away from the door latch until the gaps are less than 1 64 0 5 mm Hold the latch board tightly in this position until you check the sequence of the switches in steps 5 and 6 LATCH LATCH BOARD 0 1 64 0 1 64 Latch Board Secondary Interlock Switch Interlock Monito...

Page 24: ...ro 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 prope...

Page 25: ...on is abnormal make the necessary adjustment or replace the switch only 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 closed circuit in the door open condition When the door is closed meter should indicate an open circuit When t...

Page 26: ... each filament terminal of the magnetron and the chassis ground with an ohm mater on high test scale 1 Measure the resistance With an ohm meter on Rx1 scale a Primary winding b Filament winding c Secondary winding 2 Measure the resistance With an ohm meter on highest scale a Primary winding to ground b Filament winding to ground Normal reading Less than 1 ohm Normal reading Infinite ohms NOTE Repl...

Page 27: ...ter 1 Reverse Ohm meter Normal reading Momentarily indicates several ohms and then gradually returns to infinite ohms Abnormal reading Indicates continuity or infinite ohms from the beginning Normal readings Infinite Abnormal reading Indicates continuity Normal readings Infinite Abnormal reading continuity Normal readings continuity Abnormal reading Infinite Figure 25 a Figure 25 b Figure 26 a Fig...

Page 28: ... C N C N C Measure the resistance between terminal pins of connector KEY CONNECTOR NOTE When reconnecting the FPC connector make sure that the holes on the FPC connector are properly engaged with hooks on the plastic fastener MATRIX CIRCUIT FOR TOUCH KEY BOARD CONNECTOR KEY CON For detail matrix circuit of each model refer to page 5 2 7 17 COMPONENTS TEST PROCEDURES RESULTS TOUCH KEY BOARD Resista...

Page 29: ... is closed and START key is touched Improper operation of the primary interlock secondary interlock switches and or the interlock monitor switch Malfunction of the high voltage transformer the high voltage capacitor including the diode the magnetron the blower motor or the circuit board PROBLEMS CAUSES POWER LEVEL 1 2 3 4 5 6 7 8 9 10 4 sec 6 sec 8 sec 10 sec 12 sec 14 sec 16 sec 18 sec 20 sec 22 ...

Page 30: ...s the unit still operate GOOD Replace the circuit board Replace RELAY3 PROBLEM B TT motor and oven lamp turn on When the door is closed and START key is touched Measure the voltage at pin NO 4 of U01 Voltage reading 0 Vdc Replace the circuit board Defective RELAY3 or poor connection of RELAY3 Defective RELAY3 Replace RELAY3 or correct the connection NO NO YES YES NO NO YES YES GOOD 7 19 ...

Page 31: ...usly operates 3 Proper temperature measurement is not obtained 4 The buzzer does not sound or continues to sound 5 Some segments of one or more digits do not light up or they continue to light up or segments light when they should not 6 Wrong figures appear 7 The figures of all digits 8 Some of the indicators do no flicker light up 9 The clock does not keep time properly NOTE A MICROWAVE ENERGY LE...

Page 32: ...PERATION on page 6 1 DISPLAY Problems A thru C HELP UP Problems D thru E BUZZER Problems F WH RD Measure voltage between pin 1 and pin 3 of connector CN1 Runs Runs Runs Runs Runs 0 120 Measure resistance of touch key board after removing connector S1 See page 7 4 and 7 17 0 120 120V Replace circuit board Normal resistance Voltage incorrect Normal resistance Resistance incorrect Replace touch key b...

Page 33: ... resistance Runs Runs Runs Contact OK Replace circuit board Normal circuit board Poor contact Replace circuit board Normal circuit board Contact OK Normal contact Correct seating Check contact of connector S1 Check the contact of relay 6 see page 7 18 Measure resistance of H V Transformer see page 7 15 NO continuity PROBLEM C Unit does not heat up even if display counts down when START key is touc...

Page 34: ...7 23 PROBLEM D No buzzing when touching the key between stages or at end of cooking 1 Normal circuit board Check normal operation circuit board Replace circuit board Runs ...

Page 35: ...uns Runs Runs Runs Contact OK NO contact Replace oven thermostat Poor contact Replace circuit board Normal circuit board Contact OK Normal contact Correct seating Check contact of connector S1 see page 7 4 Replace ventilation motor ASS Y NO runs Normal ventilation motor ASS Y Check the contact of oven thermostat ...

Page 36: ...8 1 EXPLODED VIEW DOOR PARTS 13581A 13552A 13536A 13213A 14890A 13720D 13650A 14970A 14026A WTT021 ...

Page 37: ...8 2 CONTROLLER PARTS 24810P 23572A 23506A 07 268711 24781M WTP018 WTT029 ...

Page 38: ...OVEN CAVITY PARTS 36912C 33550L 63302A WTT022 WTT028 WTT029 33112U 368771 WTT029 34810T 33530A 34930R 35026G 33052A 05 34890C WTT022 35230A 63303A 34810Q 34960A WTT021 02 01 04 8 3 ...

Page 39: ...8 4 LATCH BOARD PARTS 466001 43500A 466003 466001 44510A 43501A WSZ084 ...

Page 40: ...8 5 INTERIOR PARTS I WTT021 56170D 33390G 34370T 35889A 36549S WTP013 WTT021 33740A 54810C 50CZZH WSZ002 56851D WSZ002 533001 533002 56324A WSZ002 ...

Page 41: ...8 6 INTERIOR PARTS II 56549V 56912B 53550L 55262A 55231C 56804A WTT028 WSZ002 56930V 55006F 50FZZA 568771 56411A 340511 53550F 55892A 54930F ...

Page 42: ...8 7 INSTALLATION PARTS WSZ133 WSZ204 44360A WWZ068 63300M 65862D 65862B WSZ203 WSZ098 WWZ068 63861A WSZ136 ...

Page 43: ... LO OFF HELP COOK POPCORN AUTO DEFROST LIGHT HI LO OFF CUSTOM SET REHEAT POTATO KITCHEN TIMER CLOCK LESS Ez On BEVERAGE POWER LEVEL CUSTOM COOK LIGHT TIMER N C PIZZA HOLD WARM T TABLE ON OFF STOP CLEAR START N C N C N C MORE N C N C N C N C ...

Page 44: ...8 11 PRINTED CIRCUIT BOARD ...

Page 45: ...May 2003 P NO 3828W5S3147 Printed in Korea ...

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