LG MB-308DDD Page 1 Service Manual Download | Manualshive

Page: 1 / 26

background image

MICROWAVE/ GRILL OVEN
SERVICE MANUAL

MODEL: MB-308DDD

CAUTION

BEFORE SERVICING THE UNIT, READ THE
SAFETY PRECAUTIONS IN THIS MANUAL.

1
2
3
...
»

Summary of Contents for MB-308DDD

Page 1: ...MICROWAVE GRILLOVEN SERVICE MANUAL MODEL MB 308DDD CAUTION BEFORE SERVICING THE UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL ...

Page 2: ...enings for microwave emission testing Check for microwave energy leakage after every servicing The power density of the microwave radi ation leakage emitted by the microwave oven should not exceed 4 mW cm2 And always start measuring of an unknown field to assure safety for operating personnel from radia tion leakage NOTE The standard is 5 mW cm2 while in the cus tomer s home 4 mW cm2 stated here i...

Page 3: ...n The test probe must be removed no faster than 1 inch sec 2 5 cm sec along the shaded area oth erwise a false reading may result The test probe must be held with the grip portion of the handle A false reading may result if the operator s hand is between the handle and the probe When testing near a corner of the door keep the probe perpendicular to the surface making sure the probe horizontally al...

Page 4: ...nce between the final water temperature and the ambient tem perature is 5 K The microwave power output P in watts is calculat ed from the following formula P is measured while the microwave generator is operating at full power Magnetron filament heat up time is not included about 2 sec The water is stirred to equalize temperature throughout the vessel prior to measuring the final water temperature...

Page 5: ...the oven E HIGH VOLTAGE TRANSFORMER REMOVAL 1 Discharge the high voltage capacitor 2 Disconnect the leadwire from magnetron high voltage transformer and H V capacitor 3 Remove the screws holding the high voltage trans former to the base plate F FAN MOTOR ASSEMBLY REMOVAL 1 Discharge the high voltage capacitor 2 Disconnect the leadwire from fan motor noise filter asm and H V capacitor 3 Remove the ...

Page 6: ...agnetron Microwave energy must be below the limit of 5mW cm2 With a 275 ml water load Make sure that gasket is rigidly attached to the magnetron To prevent microwave leakage tight en the mounting screws properly making sure there is no gap between the waveguide and the magnetron J REMOVING THE TURNTABLE MOTOR 1 Remove the turntable 2 Remove the turntable shaft VERY CAREFULLY with a slotted screwdr...

Page 7: ...ITCH TO THE LATCH BOARD 3 INSTALLATION AND ADJUSTMENT OF THE LATCH BOARD TO THE OVEN ASSEMBLY Mount the latch board to the oven assembly Adjust the latch board in the arrow direction so the oven door will not have any play in it when the door is closed Tighten the mounting screw Check for playing in the door by pushing the door release button Door movement should be less than 0 5mm 1 64 inch Do no...

Page 8: ...is closed meter should indicate a 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 close NC terminals of the switch The meter should indicate closed circuit in the door op...

Page 9: ... THE OVEN COMPONENTS TEST PROCEDURE RESULTS HIGH VOLTAGE TRANSFORMER Wire leads removed MAGNETRON Wire leads removed 1 Measure the resistance Multi meter scale Rx1 Primary winding Secondary winding Filament winding 2 Measure the resistance Multi meter scale Rx1000 Primary winding to ground Filament winding to ground 1 Measure the resistance Multi meter scale Rx1 Between filament terminals 2 Measur...

Page 10: ...le Rx1000 Terminal to case Measure the continuity Forward Multi meter scale Rx10000 Measure the continuity Reverse Multi meter scale Rx10000 Normal Momentary indi cates several ohms and then gradually returns to infinite Normal Normal Continuity Abnormal Normal Abnormal Continuity NOTE When testing the magnetron be sure to install the magnetron gasket in the correct position and be sure that the g...

Page 11: ... V D and H V C before replacing the fuse If the fuse is blown by improper switch operation replace the defective switch and the fuse at the same time Replace just the fuse if the switches operate normally HEATER ELEMENT Wire leads removed MAGNETRON THERMOSTAT OVEN THERMOSTAT FUSE Wire leads removed NOTE Make sure heater is fully cooled when tested Normal Gill heater Approx 55 Ω at 20 30 C Normal m...

Page 12: ... TURNTABLE MOTOR Wire leads removed RELAY OF P C B Disconnect the 5 pin connector from P C B RELAY 2 RELAY 3 OF P C B Wire leads removed Note Relay Relay 1 Fan motor Turntable motor Oven lamp Relay 2 Microwave Relay 3 Grill NOTE 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...

Page 13: ...o discharge any static charge built up in your body CONDITION Microwave oven does not work Inserting many plug into one plug outlet and using them at the same time causes overloading Microwave oven plug is not inserted tightly Output power is too low Low AC input voltage Food temperature is too low Using metallic ware and allowing it to touch the oven wall Sparks occuring Inconsistent intensity of...

Page 14: ...ing cooking cycle 11 Display time of day does not reappear when cooking is finished 12 Beep sound is not heard when correct key is touched TROUBLE 1 The following visual conditions indicate a probable defective control circuit CONDITION CHECK RESULT CAUSE REMEDY 1 No input can be programmed Certainly No certainly Defective PCB assembly Loose connec tion Replace PCB assembly Connect them tightly Ch...

Page 15: ...with door closed Check continuity of primary switch with door opened Disconnect one side of the wire lead connected from transformer to the high voltage capacitor and operate the unit Replace fuse 2 Fuse does not blow No continuity Continuity No continuity Defective power supply cord Replace power supply cord Defective mag netron thermostat Replace magen tron thermostat Check continuity of magnetr...

Page 16: ...TROUBLE 3 Display shows all figures set but oven does not start cooking while desired program times are set and START pad is touched TROUBLE 4 Oven seems to be operating but little heat is produced in oven load NOTE Simple test of power output conducted by heating one liter water for one min if available Minimum 8 5 C temperature rise is normal condition CONDITION CHECK RESULT CAUSE REMEDY Output ...

Page 17: ...erates properly Abnormal Defective H V circuit protector Replace H V circuit protector Normal Check H V circuit protector Abnormal Defective high voltage trans former Replace high voltage trans former Normal Check high volt age transformer Abnormal Defective high voltage capacitor Replace high voltage capacitor Normal Check high volt age capacitor Abnormal Defective high voltage diode Replace high...

Page 18: ...function the heater Replace Heater Normal No continuity Open or loosen Replace or connect tightly Wire connection TROUBLE 7 Grill NOTE MAKE SURE THE WIRE LEADS CORRECT POSITION WHEN REMOVING THE WIRE LEADS FROM THE PARTS BE SURE TO GRASP THE CONNECTOR NOT THE WIRES WHEN REMOVING THE MAGNETRON BE SURE TO INSTALL THE MAGNETRON GASKET IN THE CORRECT POSITION AND IN GOOD CONDITION 2 Lower tempera ture...

Page 19: ...6 1 INTRODUCTION EXPLODED VIEW DOOR PARTS CONTROLLER PARTS LATCH BOARD PARTS BASE PLATE PARTS INTERIOR PARTS OVEN CAVITY PARTS ...

Page 20: ...6 2 1 DOOR PARTS ...

Page 21: ...6 3 2 CONTROL PANEL PARTS ...

Page 22: ...6 4 3 OVEN CAVITY PARTS WSZ002 33052M WTT010 33112U WTT021 33390G 35889A 34370T 35026G WTP013 54974A 36549S 35301A 33461Z 34774U 348101 35300A WTT021 WSZ059 35300A 349601 ...

Page 23: ...6 5 4 LATCH BOARD PARTS WSZ002 WTT028 WSZ084 466001 466003 466001 43500A 466001 ...

Page 24: ...TS WSZ002 WSZ002 55263A 56912B 948501 WTT028 WSZ002 568711 50FZZA 56930M 56930G 54826A 948502 55006F 56930V 56411A WSZ062 WTT037 56549F WSZ112 WSZ002 WTT028 948503 56324A 54810C 56549S 55900A WSZ002 50CZZH 56851C 56851D ...

Page 25: ...6 7 6 BASE PLATE PARTS 56170D WSZ002 63302A 34774U 647781 WSZ085 WTT030 WSZ062 WTT002 ...

Page 26: ...6 8 PACKING AND ACCESSORIES PACKING UPPER PE FILM FILAMENT TAPE PE BAG PACKING BASE BOX PACKING TABLE 2 GLASS TRAY GRILL RACK PRINTING MATERIAL ROTATING RING PACKING TABLE 1 ...

Reviews:

No comments

Related manuals for MB-308DDD

Brand: Oster Pages: 34

Brand: Rangemaster Pages: 40

Brand: Baumatic Pages: 20

Brand: Daewoo Pages: 37

Brand: Watlow Electric Pages: 23

Brand: MAISTERmicro Pages: 24

Brand: Dacor Pages: 8

Brand: Tesco Pages: 12

Brand: Duke Pages: 29

Brand: Blodgett Pages: 2

Brand: Magic Chef Pages: 32

Brand: Cuisinart Pages: 40

Brand: Falcon Pages: 12

Brand: Samsung Pages: 433

Brand: Samsung Pages: 104

Brand: Doyon Pages: 60

Brand: Hamilton Beach Pages: 14

Brand: Toastmaster Pages: 16

Brands by name

0 1 2 3 4 5 6 7 8 9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Popular brands

Load more brands