LG Electronics LRMM1430SB manual

MICROW A VE OVEN SER VICE MANUAL MODEL : LRMM1430SW LRMM1430SB CAUTION BEFORE SERVICING THE UNIT , READ THE SAFETY PRECAUTIONS IN THIS MANUAL. website http://www.lgservice.com[...]

-1- CAUTION W ARNING T O SER VICE TECHNICIANS PRECAUTIONS T O BE OBSER VED BEFORE AND DURING SER VICING T O A VOID POSSIBLE EXPOSURE T O EXCESSIVE MICROW A VE ENERGY a. Do not operate or allow the oven to be operated with the door open. b. Make the following safety checks on all ovens to be serviced before activating the magnetron or other microwav[...]

FOREWORD Read this Manual carefully. Failure to adhere to or observe the information in this Manual may result in exposing yourself to the Microwave Energy normally contained within the oven cavity. MECHANICAL SERVICE INFORMATION T ABLE OF CONTENTS 1. Adjustment Procedures ............................................................................[...]

-3- 1. ADJUSTMENT PROCEDURES To avoid possible exposure to microwave energy leakage, adjust the door latches and interlock switches, using the following procedure. ONLY AUTHORIZED SERVICE PERSONNEL SHOULD MAKE THIS ADJUSTMENT. The Interlock Monitor and Primary Interlock Switch acts as the final safety switch protecting the user from microwave energ[...]

-4- LA TCH BOARD PRIMARY INTERLOCK SWITCH LA TCH LA TCH BOARD (A) (B) 0-1/64" 0-1/64" DOOR LA TCH SECONDARY INTERLOCK SWITCH MONITOR INTERLOCK SWITCH Figure 1-a Figure 1-b[...]

2. PRECAUTIONS ON INST ALLA TION (Figure 2) A. Plug the power supply cord into a 120 V AC, 60 Hz, single-phase power source with a capacity of at least 20 amperes. B. Since the unit weights about 38 lbs., be sure to place it on a sturdy and flat surface. C. Avoid placing the unit in a location where there is direct heat or splashing water. D. Place[...]

SPECIFICA TIONS Rated Power Consumption 1250W maximum Output 1200W maximum ( * IEC 60705 Rating standard) Adjustable 0W through 1200W, 10 steps Frequency 2,450 MHz 50 MHz Power Supply 120V 12V AC, 60Hz Rated Current 11 Amp. Magnetron Cooling Forced Air Cooling Microwave Stirring Turntable Rectification Rectification Voltage Doubler Half-Wave (Inver[...]

6. OVERALL CIRCUIT DIAGRAM A. SCHEMA TIC DIAGRAM -7- Figure 3[...]

B. MA TRIX CIRCUIT FOR TOUCH KEY BOARD -8- Figure 4[...]

7. OPERA TING PROCEDURES A. CONTROL P ANEL Figure 5. -9- 1. Display. The Display includes a clock and indicators that tell you time of day, cooking time settings, and cooking functions selected. 2. Sensor Touch. This pad allows you to cook most of your favorite foods without having to select cooking times and power levels. 3. Homemade Bakery. Homem[...]

B. PANEL INSTRUCTIONS (Figure 5) The entire operation is done by simple touch control pads. (1) Display Window Numbers and letters explained in Figure 5 are shown in the display window (Vacuum Fluorescent Tube). (a) The Time in four digits (12-hour indication): 00 Hour 00 Minute. (b) Cooking Time of Day in four digits 00 Minutes 00 Seconds. (c) Pow[...]

C. EASY USE CHART (1) CLOCK 1. Touch STOP/CLEAR. 2. Touch CLOCK. 3. Touch numbers for correct time of day. 4. Touch CLOCK. (2) “HI-POWER” COOKING 1. Touch STOP/CLEAR. 2. Touch COOK TIME. 3. Touch numbers for desired cooking time. 4. Touch START. (3) “MULTI-STAGE” COOKING 1. Touch STOP/CLEAR. 2. Touch COOK TIME. 3. Touch numbers for cooking [...]

8. PROCEDURE FOR MEASURING MICROW A VE ENERGY LEAKAGE A. CAUTIONS (1) Be sure to check a microwave emission prior to servicing the oven if the oven is operative prior to servicing. (2) The service personnel should inform the manufacturer, importer, or assembler of any certified oven unit found to have a microwave emission level in excess of 5mW/cm.[...]

D. MEASUREMENT WITH A FULLY ASSEMBLED OVEN (1) After all components, including the outer panels, are fully assembled, measure for microwave energy leakage around the door viewing window, the exhaust opening and air inlet openings. (2) Microwave energy leakage must not exceed the values prescribed below. NOTES: Leakage with the outer panels removed [...]

-14- 9. DISASSEMBL Y INSTRUCTIONS IMPORTANT NOTES: UNIT MUST BE DISCONNECTED FROM ELECTRICAL OUTLET WHEN MAKING REPAIRS, RE-PLACEMENTS, ADJUSTMENTS AND CONTINUITY 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.[...]

C. REMOVING CONTROL CIRCUIT BOARD (Figure 10) (1) Remove out case. (2) Remove door assembly. (3) Unfasten two screws. (4) Lift up and pull out control panel assembly carefully from the cavity. (5) Remove door frame. (6) Remove the F.P.C connector from the terminal socket. (7) Unfasten two screws which tighen the circuit board. (8) Remove control ci[...]

-16- E. AIR GUIDE REMOVAL (Figure 12) (1) Separate cavity and base plate. (2) Unfasten the screws which hold the air guide in the base plate. (3) Unfasten the air guide from hook. F. POWER BOARD AND INVERTER MODULE AND SUCTION GUIDE (Figure 12) (1) Separate cavity and base plate. (2) Remove air guide. (3) Unfasten the screws. (4) Lift up the power [...]

-17- H. MAGNETRON REMOVAL (1) Disconnect the leadwire from the magnetron. (2) Carefully remove the mounting screws holding the magnetron at the waveguide. (3) Remove the magnetron from the waveguide. NOTE: 1. When removing the magnetron, make sure its dome does not hit any adjacent parts, or it may be damaged. 2. When replacing the magnetron, be su[...]

J . FAN MOTOR ASSEMBLY REMOVAL ( 1) Separate cavity and base plate. ( 2) Remove air and suction guide.. ( 3) Remove the two screws holding the fan motor ASSEMBLY to the suction guide ASSEMBLY . ( 4) Disconnect the wires and unfasten the screws. ( 5) Pull out the Fan motor from the suction guide. K. INTERLOCK SYSTEM (1) INTERLOCK MECHANISM The door [...]

-19- A. PRIMARY INTERLOCK SWITCH TEST When the door release button is depressed slowly with the door closed, an audible click should be heard at the same time or successively at intervals. When the button is released slowly, the latches should activate the switches with an audible click . If the latches do not activate the switches when the door is[...]

-20- CAUTIONS 1. DISCONNECT THE POWER SUPPLY CORD FROM THE OUTLET WHENEVER REMOVING THE OUTER CASE FROM THE UNIT. PROCEED WITH THE TEST ONLY AFTER DISCHARGING THE HIGH VOLTAGE CAPACITOR AND REMOVING THE LEAD WIRES FROM THE INVERTER MODULE. 2. ALL OPERATIONAL CHECKS WITH MICROWAVE ENERGY MUST BE DONE WITH A LOAD (1 LITER OF WATER IN CONTAINER) IN TH[...]

-21- COMPONENTS TEST PROCEDURE RESULTS SENSOR Normal: Approximately BK-RD: 5.2 Kohms RD-WH: 2.1 Kohms BK-WH: 2.1 Kohms Abnormal: Infinite or several *Sensor cooking condition 1. Oven should be plugged in at least 5 minutes before sensor cooking. 2. Room temperature should not exceed 95 ˚ F. 3. Be sure the exterior of the cooking container and the [...]

-22- COMPONENTS TEST PROCEDURE RESULTS RELAY FAN MOTOR (Wire leads removed) TURNTABLE MOTOR (Wire leads removed) Check for continuity of relay with an ohm-meter. (Remove lead wires from relay and operate the unit.) Measure the resistance. (Ohm-meter scale: R x 100) Measure the resistance. (Ohm-meter scale: R x 1000) Normal: Approx. ON: 0 ohm OFF: ?[...]

-23- B. CHECKOUT PROCEDURES (1) CHECKOUT PROCEDURES FOR FUSE BLOWING CAUTION: REPLACE BLOWN FUSE WITH 20 AMPERE FUSE. Fuse blows immediately after the door is closed. Fuse blows immediately after the door is opened. Fuse blows when the door is closed and START key is touched. Improper operation of the primary interlock, secondary interlock switches[...]

-24- (2) CHECKOUT PROCEDURES FOR RELAY - PROBLEM (A) - FAN motor and oven lamp turn on without touching START key when the door is closed. Remove the mate connector of I/O CON from the circuit board does the unit still operate? GOOD GOOD Replace the circuit board - PROBLEM (B) - FAN motor and oven lamp turn on When the door is closed and START key [...]

(3) CHECKOUT PROCEDURES FOR CIRCUIT BOARD The following symptoms indicate a defective circuit board. (1) Check the input current. If the input current is more than 20A, check the magnetron and wiring. If the input current is less than 0.5 A, there is no input to the inverter. (2) The start function fails to operate but the interlock switches, the d[...]

-26- C. TROUBLE SHOOTING WHEN YOU GET A COMPLAINT FROM YOUR CUSTOMER, EVALUATE THE COMPLAINT CAREFULLY. IF THE FOLLOWING SYMPTOMS APPLY, PLEASE INSTRUCT THE CUSTOMER IN THE PROPER USE OF THE MICROWAVE OVEN. THIS CAN ELIMINATE AN UNNECESSARY SERVICE CALL. CAUTIONS 1. Check grounding before checking for trouble. 2. Be careful of the Inverter. 3. When[...]

-27- 1. Incomplete segments. • Segment missing. • Partial segment missing. • Digit flickering (NOTE: Slight flickering is normal.) 2. Colon does not turn on or blink. 3. A distinct change in the brightness of one or more numbers in display. 4. One or more digits in the display are not lighting. 5. Display indicates a number different from one[...]

-28- CONDITION CHECK RESULT CAUSE REMEDY 1. Fuse blows. Continuity. No continuity. Continuity. Shorted contact at the primary switch. Replace fuse, primary, monitor switches, and RELAY of P.C.B Assembly. No continuity. Normal. Defective control PCB. Replace Inverter. Fuse blows again Defective Inverter. Replace control PCB. Malfunction of the monit[...]

-29- CONDITION CHECK RESULT CAUSE REMEDY 1. Setting time does not count down when touching START pad. 2. Fan motor or oven lamp do not turn on. No continuity. Continuity. Continuity Defective Power PCB assembly. Loose connection. Replace Power PCB assembly. Connect them tightly. No continuity Abnormal Check fan motor. Defective fan motor. Replace f[...]

-30- CONDITION CHECK RESULT CAUSE REMEDY No microwave oscillation. No continuity. Continuity. Defective PCB assembly. Replace PCB assembly. Disconnect the wire leads from relay and check continuity of relay. ( O perate the unit) Replace Inverter and Magnetron. Output is full power when you set lower power level. Abnormal. Defective PCB assembly. Re[...]

-31- INTRODUCTION EXPLODED VIEW[...]

-32- DOOR P ARTS 14970A 14026A WTP002 13806A 13213A 13552A 13536A 13581A 268711 WTP002 23506A 13551A 15006A[...]

-33- CONTROLLER P ARTS 268711 WTP002 23506A 13551A[...]

-34- OVEN CA VITY P ARTS 33112U WTT022 :Model LRMM 1430SW :Model LRMM 1430SB W107 33390G 35889A WSZ185 36549S WTP013 33052A 13806F 647781[...]

-35- LA TCH BOARD P ARTS WSZ085 43500A 466001 43501A 466003 466001[...]

-36- OVEN INTERIOR P ARTS WTT028 WTT021 54974T 56501A 56930V 56912B 43500A 56324A WSZ002[...]

-37- BASE PLA TE P ARTS 35264A 568772 568771 56549F 56851H 56201A 50FZZA 54980A 43501A 65006B 63302A WTT021 WTT028 WTT034 WSZ002 268712 WTT028 WTT028 WTT028 55900A 54974S 55238A 568711 56411A[...]

-38- REPLACEMENT P AR TS LIST LOC. NO. *01 3828W5A3194 MANUAL,OWNERS R *02 3828W5S3066 MANUAL,SERVICE R *10 3890W3W376B BOX,WHITE R 13213A 3213W0A008B DOOR FRAME ASSEMBLY R 13536A 3536W1A002A SEAL TAPE S 13552A 3552W0A009A CHOKE COVER R 13581A 3581W0A077B DOOR ASSEMBLY R 13806F 3806W1A062A DECO,FRONT R 14026A 4026W1A025A LATCH R 14970A 4970WRA001C [...]

-39- LOC. NO. WTP002 1TPL0302018 SCREW TAPPING,PAN HEAD R WTP013 1TPL0402418 SCREW TAPPING,PAN HEAD R WTT021 1TTL0402418 SCREW TAPPING,TRUSS HEAD R WTT028 1TTL0402818 SCREW TAPPING,TRUSS HEAD R WTT034 1TTL0403418 SCREW TAPPING,TRUSS HEAD R PART NO. DESCRIPTION SVC ALTER R,S: SERVICE PARTS[...]

-40- LOC. NO. *01 3828W5A3340 MANUAL,OWNERS R *02 3828W5S3192 MANUAL,SERVICE R *10 3890W3W377A BOX,WHITE R 13213A 3213W0A008C DOOR FRAME ASSEMBLY R 13352A 3352W1A144A FRONT SCREEN S 13536A 3536W1A002A SEAL TAPE S 13552A 3552W0A009A CHOKE COVER R 13581A 3581W0A077E DOOR ASSEMBLY R 13720D 3720W0D308A PANEL,DOOR R 13806F 3806W1A062B DECO,FRONT R 14026[...]

-41- LOC. NO. WTP002 1TPL0302018 SCREW TAPPING,PAN HEAD R WTP013 1TPL0402418 SCREW TAPPING,PAN HEAD R WTT021 1TTL0402418 SCREW TAPPING,TRUSS HEAD R WTT022 1TTL0402422 SCREW TAPPING,TRUSS HEAD R WTT028 1TTL0402818 SCREW TAPPING,TRUSS HEAD R WTT034 1TTL0403418 SCREW TAPPING,TRUSS HEAD R PART NO. DESCRIPTION SVC ALTER R,S: SERVICE PARTS[...]

-42- SCHEMA TIC DIAGRAM OF P .C.B[...]

-43- PRINTED CIRCUIT BOARD KEY PCB MAIN PCB[...]

-44- P .C.B. P AR TS LIST LOC. PART NO. DESCRIPTION SPECIFICATION SVC ALTER NO. AR1 0RZ1503G610 RESISTOR,DRAWING 150KOHM 1/4W 5% 3216 BULK 8 PIN R BZ1 6908W3YA01C BUZZER TFM-57 CW NINGBO EAST PIEZO 2048HZ 70D R 6908W3YA01A C01 0CK1040K948 CAPACITOR,FIXED CERAMIC(HIGH DIELECTRIC) 0.1UF D 50V 80%,-20% F(Y5V) TA26 R C02 0CE2276K618 CAPACITOR,FIXED ELE[...]

-45- LOC. PART NO. DESCRIPTION SPECIFICATION SVC ALTER NO. D61 0DD414809AA DIODE,SWITCHING 1N4148 ROHM TP26 DO35 100V 450MA 2A 3NS R D90 0DD414809AB DIODE 1N4148M PYUNG CHANG TP26 DO34 60V 0.5A 0 R D91 0DD414809AB DIODE 1N4148M PYUNG CHANG TP26 DO34 60V 0.5A 0 R D92 0DD414809AB DIODE 1N4148M PYUNG CHANG TP26 DO34 60V 0.5A 0 R D93 0DD414809AB DIODE [...]

-46- LOC. PART NO. DESCRIPTION SPECIFICATION SVC ALTER NO. R38 0RD5601G608 RESISTOR,FIXED CARBON FILM 5.6K OHM 1/4 W 5% TA26 R R39 0RD1002F608 RESISTOR,FIXED CARBON FILM 10K OHM 1/6 W 5% TA26 R R45 0RD4702F608 RESISTOR,FIXED CARBON FILM 47K OHM 1/6 W 5% TA26 R R46 0RD3302F608 RESISTOR,FIXED CARBON FILM 33K OHM 1/6 W 5% TA26 R R47 0RD1001F608 RESIST[...]

P/NO : 3828W5S3066 May , 2003 Printed in Korea[...]