manualshive.com logo in svg

LG LMV1314B, Service Manual

Share
Download
LG LMV1314B Service Manual Download Page 32

7-21

PROBLEM

-C

:

Displa

y does not star

t countdo

wn when ST

AR

T k

e

y

 is touched.

PROBLEM

-D

:

Unit oper

ation 

seems to be nor

mal 

b

ut 

little or

no heating is produced in o

v

en load.

Chec

k:

  1.

  

T

OUCH KEY BO

ARD (ST

AR

T KEY FUNCTION)

Chec

k:

  1.

  AIR 

VENTS

1

1

Chec

k contin

uity of connector

CN2 betw

een Pin 1(PK) and

pin 3(BL) when the door is

closed

Chec

k oper

ation of f

a

n

motor when ST

AR

T k

e

y

is touched.

Contin

uity

OK

Chec

k contact of

connector S1

Contact

OK

Replace 

Circuit board

Correct

seating

Nor

m

al

circuit board

Nor

m

al

contact

P

oor

contact

Nor

m

al Pr

imar

y 

s

witch

No

contin

uity

Adjust or replace door

sensing s

witch.

Measure resistance

of H.V

.capacitor

(see page 7-16)

Resistance

incorrect

Nor

m

al

resistance

Nor

mal 

oper

ation

No

oper

ation

Replace

ther

mostat

Nor

mal

ther

mostat

Measure resistance

of f

an motor

38

8 ohms

Resistance

incorrect

Replace 

fan motor

Nor

m

al 

fan motor

Nor

m

al 

circuit board

Replace

circuit board

Nor

m

al

resistance

Replace H.V

.C

.

Nor

mal H.V

.C

.

Nor

m

al

magnetron

Replace

magnetron

Nor

mal

oper

ation

No

oper

ation

THERMOST

A

T

J

u

mper across

ter

minals of

THERMOST

A

T

 b

y

 

using jumper lead

Runs

Runs

Runs

Runs

Runs

Runs

Runs

Runs

33

Summary of Contents for LMV1314B

Page 1: ...VE OVEN SERVICE MANUAL MODEL LMV1314B CAUTION website http biz LGservice com e mail http www LGEservice com techsup html BEFORE SERVICING THE UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL LMV1314W LMV1314SV ...

Page 2: ...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 each ove...

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 11 INTERLOCK CONTINUITY TEST 7 13 TEST AND CHECKOUT PROCE...

Page 4: ...C 4 C Oven Cavity Thermostat Open at 90 C 4 C Fuse 20A Primary Interlock Switch Secondary Interlock Switch Interlock Monitor Magnetron 2M214 5129F High Voltage Capacitor Capacitor 0 95µF 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 mm 99 sec in each cooking stage Tray Tempered Safety Glass Overall Dimensions 217 8 W x165 8 D...

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: ...t 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 ground...

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

Page 8: ...y weight 10 FROZEN ENTREE Touch this pad to reheat 10 oz 11 FRESH VEGETABLE Touch this pad to cook from 1 to 4 cups 12 NUMBER Touch number pads to enter cooking time power level quantities or weights 13 POWER Touch this pad to select a cooking power level 14 TIME Used to set manual time cooking 15 STOP CLEAR Touch this pad to stop the oven or to clear all entries 16 START Touch this pad to start a...

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

Page 10: ...TIMER Ez On CUSTOM SET FRESH VEGETABLE 5 2 MATRIX CIRCUIT FOR TOUCH KEY BOARD ...

Page 11: ...condary 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 the unit Two short and a long beep sound signal is heard when the time is up The unit will shut off automatically F Confirm the water is hot G Finally measure the output power according to POWER OUTPUT MEASURE...

Page 12: ... 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 any other visible damage on the unit that may cause microwave ...

Page 13: ... for microwave leakage after every servicing The power density of the microwave radiation leakage emitted by the 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...

Page 14: ...rgy leakage not be more than 2 mW cm2 after determining that all parts are in good condition functioning properly and genuine replacement parts which are listed in this manual have been used 3 At least once a year have the electromagnetic energy leakage monitor checked for calibration by its manufacturer 1 Microwave power output measurement is made with the microwave oven supplied at its rated vol...

Page 15: ...CHES 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 three connectors CN1 and wire leads Relay2 and or Relay5 from the circuit board 4 Remove 2 or 3 screws securing the circuit board 5 Remove the FPC connector from the terminal...

Page 16: ... 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 o...

Page 17: ...hem to the out case on the base plate Remove the mount all from the out case by removing two screws securing it to the out case 5 Remove four screws securing them to the back plate 6 Slap the both side of out case backward by 1 2 inches 7 Disconnect the power cord connector from the noise filter and remove the earth screw 8 Remove the out case with pushing it backward completely Vent Grille Contro...

Page 18: ...condary Interlock Switch Monitor Interlock Switch Primary Interlock Switch Latch Board GR from P C B GR from earth PK from P C B Secondary Interlock Switch Monitor Interlock Switch Primary Interlock Switch BR from Relay 2 YL from Fan Motor WH from Cook top Lamp BK from Noise Filter BR from H V Transformer BK from Relay2 YL from Base Thermostat RD from H V Transformer Figure 9 Figure 10 WIRE COLOR ...

Page 19: ...nd pull it to the right very carefully NOTES When removing 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 Check microwave energy ...

Page 20: ...Y See Figure 16 Flat blade screw driver Mount all Figure 15 Figure 16 Space E REMOVING DOOR Figure 13 1 Remove the vent grille by removing two screws securing it to the front of the out case 2 Remove the door cap with small screw driver 3 Lift up and push the door F DISASSEMBLING DOOR Figure 14 1 Remove the choke cover by using knife blade or small screw driver etc CAUTION Be careful not to damage...

Page 21: ...ecuring it to the oven cavity Figure 17 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 18 NOTES Remove the leadwire from the turntable motor VERY CAREFULLY Be sure to grasp the connector not the wires when removing 7 10 Wire Leads Turntable Motor Figure 18 Figure 17 ...

Page 22: ...ps 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 sequence of the switches NOTE To correct sequence of the Primary Interlock Switch Secondary Interlock Switch and the Interlock Monitor Switch is very important If any gap is larger than 1 64 0 5 mm you will need to adjust the latch board Go to step 3 and follow all steps in order ADJUST...

Page 23: ...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 24: ...n closed circuit When the secondary switch operation 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 c...

Page 25: ... 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 26: ...tinuity 1 Forward Ohm meter Figure 24 1 Reverse Ohm meter Figure 25 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 Infi...

Page 27: ...e resistance between terminal pins of connector KEY CON 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 Figure 26 Resistance value When When not touched touched Less than More than 400 ohms 1 mega ohm 1 2 3 4 5 6 7 8 9 10 11 12 13 FPC CONNECTOR Top Fig...

Page 28: ...eration 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 sec 18 sec 16 sec 14 sec 12 sec 10 sec 8 sec 6 ...

Page 29: ... the circuit board Does the unit still operate GOOD Replace the circuit board PROBLEM B FAN motor and oven lamp turn on When the door is closed and START key is touched Measure the voltage at pin NO 36 of U01 Voltage reading 0 Vdc Replace the circuit board Defective RELAY1 or poor connection of RELAY1 Replace RELAY1 or correct the connection NO NO YES NO NO YES YES GOOD ...

Page 30: ...he interlock switches the door sensing and the relay check good 2 The unit with a normal relay continuously 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 t...

Page 31: ...PERATION on page 6 1 DISPLAY Problems A thru C BUZZER Problems F HELP UP Problems D thru E 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 16 0 120 120V Replace circuit board Normal circuit board Normal resistance Voltage incorrect Normal resistance Resistance incorrec...

Page 32: ...rrect seating Normal circuit board Normal contact Poor contact Normal Primary switch No continuity Adjust or replace door sensing switch Measure resistance of H V capacitor see page 7 16 Resistance incorrect Normal resistance Normal operation No operation Replace thermostat Normal thermostat Measure resistance of fan motor 38 8 ohms Resistance incorrect Replace fan motor Normal fan motor Normal ci...

Page 33: ...ect Normal H V C Abnormal Replace H V D Normal Magnetron Replace Magnetron Normal Normal H V D Check the continuity of H V D see page 7 16 Replace H V C Normal resistance Replace H V T Normal resistance NO continuity 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 Runs Runs Ru...

Page 34: ...7 23 PROBLEM F 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 Contact OK NO contact Replace magnetron thermostat Poor contact Replace circuit board Normal circuit board Contact OK Normal contact Correct seating Check contact of connector S1 see page 7 4 Runs Replace ventilation motor ASS Y NO runs Normal ventilation motor ASS Y Check the contact of magnetron thermostat ...

Page 36: ...8 1 EXPLODED VIEW DOOR PARTS 14890A 13536A 13552A 14970A 15006A 13213A 13720D 13581A 14026A ...

Page 37: ...8 2 CONTROLLER PARTS 24810P 23506A 23572A 24781M 268711 250201 24970A 24510L WTP018 ...

Page 38: ... 34960A WSZ197 33112U 33530A 34890C 34810T WTT022 63302A 35230A 63303A 33052M WTT022 53550L 368771 56804A 340511 For model WSZ198 For model LMV1314W WTT027 For model LMV1314B LMV1314SV LMV1314B LMV1314SV WTT029 For model LMV1314W ...

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

Page 40: ...8 5 INTERIOR PARTS I 33390G 34036W 36549S WTP013 WSZ137 56170D 53300B 35889A 56930G WTT021 30RMZZ 54974A 56201B 56324A WSZ002 ...

Page 41: ...8 6 INTERIOR PARTS II 55262A 53550A 36549V 54810C WTT028 56851D 56411A WTT033 50CZZH 56912B 56930V 44360A 56549F 568771 56930M 56201A 55900A WSZ002 50FZZA ...

Page 42: ...8 7 INSTALLATION PARTS 63301M 65862B WTT028 65862D ...

Page 43: ...8 14 SCHEMATIC DIAGRAM OF P C B ...

Page 44: ...8 15 PRINTED CIRCUIT BOARD ...

Page 45: ...P NO 3828W5S3426 Oct 2003 Printed in Korea ...

Reviews:

No comments

Brands by name

Popular brands

Load more brands