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Microwave Oven
Service Manual

JVM1790BK/CK/SK/WK

CAUTION

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

Summary of Contents for JVM1790BK - Profile 1.7 cu. Ft. Convection Microwave

Page 1: ...삼 흥 정 판 Microwave Oven Service Manual JVM1790BK CK SK WK CAUTION BEFORE SERVICING THE UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL ...

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: ... 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 PROCEDURES AND TROUBLE SHOOTING 7 15 A TEST PROCEDURES 7 15 B CHECKOUT PROCEDURES 7 19 C TROUBLE SHOOTING 7 24 EXPLODED VIEW 8 1 PART REFERENCE LIST 9 1 SCHEMATIC DIAGRAM OF PCB 10 1 PRINTED CIRCUIT BO...

Page 4: ...150 C 6 C Oven Cavity Thermostat Open at 145 C 6 C Fuse 20A Primary Interlock Switch Secondary Interlock Switch Interlock Monitor Magnetron 2M246 21CT High Voltage Capacitor Capacitor 0 95µF 2 1 KV AC High Voltage Diode Diode 350mA 9 0 KV Cook top Lamp 130 V 50 W Cavity Lamp 130 V 35 W Timer Digital up to 95 mim 00 sec in each cooking stage Tray Tempered Safety Glass Overall Dimensions 2915 16 W x...

Page 5: ... 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 2 1 CAUTIONS Unlike other appliances the microwave oven is high voltage and high current equipment Though it is free fro...

Page 6: ...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 3 1 INSTALLATIONS BEFORE YOU BEGIN READ THE FOLLOWING INSTRUCTIONS COMPLETELY AND CAREFULLY CAUTION This unit is equipped with a 3 prong plug for your safety If the wall outlet is a grounded 3 hole type the unit will be grounded aut...

Page 7: ...4 1 OPERATING INSTRUCTIONS CONTROL PANEL For Model JVM1790BK JVM1790CK JVM1790SK JVM1790WK ...

Page 8: ...h this pad to reheat leftovers The oven s sensor will tell the oven how long to cook depending on the amount of humidity coming from the food 8 WARM Touch this pad to warm 9 DEFROST Touch this pad to select food type and defrost food by weight 10 TIMER Touch this pad to set the timer 11 CLOCK AM FM Touch this pad to enter the time of day 12 OPTION Touch this pad to change the oven s default settin...

Page 9: ...AGRAM SCHEMATIC DIAGRAM ERROR MODE DISPLAY F1 F2 F3 F4 F5 THERMAL SENSOR OPEN THERMAL SENSOR SHORT KEYPANEL SHORTED FOR 60 SECONDS HUMIDITY SENSOR OPEN HUMIDITY SENSOR SHORT For Model JVM1790BK JVM1790CK JVM1790SK JVM1790WK ...

Page 10: ...5 2 MATRIX CIRCUIT FOR TOUCH KEY BOARD For Model JVM1790BK JVM1790CK JVM1790SK JVM1790WK ...

Page 11: ... is closed E Continue operating the unit Four 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 MEASUREMENT on page 7 3 FEATURES AND SPECIFICATIONS FEATURES A The safety systems incorporated in this model are 1 Primary interlock switch 2 Secondary interlock switch 3 Interl...

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: ...hould 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 MICROWAVE ENERGY L...

Page 14: ...exceed meter full scale deflection 2 The test probe must be removed no faster than 1 inch sec 2 5cm 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 s hand is between the handle and the probe 4 When testing near a corner of the door keep the probe perpendicular to the surface ...

Page 15: ...Figures 1 2 and 3 1 Disconnect power at the main fuse or circuit breaken or pull the plug Remove the top grille by removing the two screws that hold it in place 2 Remove a screw securing the control panel assembly to the oven cavity 3 Remove the control panel with pushing it upward 4 Remove the six connectors CN1 CN2 CN3 CN5 CN6 CN8 and wire leads Relay2 Relay11 from the circuit board 5 Remove 7 s...

Page 16: ...CONNECTOR Follow the steps below as illustrated in Figures 6 and 7 to insert the F P C connector 1 Insert the 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 pro...

Page 17: ...uate support to prevent dropping unit during removal C REMOVING THE OUT CASE Figure 8 1 Remove the vent grille by removing two screws securing it to the out case 2 Remove two screws securing it to the air duct 3 Remove the base plate by removing four 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 4 Remove four screws fro...

Page 18: ...ge 7 12 Latch Board Primary Interlock Switch Interlock Monitor Switch Secondary Interlock Switch Latch Board BK CN1 RD Bottom TCO RD H V Transformer WH from Convection Heater Primary Interlock Switch Monitor Interlock Switch Secondary Interlock Switch PK from P C B GN from P C B WH from H V Transformer RD from H V Transformer Figure 9 Figure 10 WIRE COLOR SYMBOL COLOR WH BK BR RD BL PK GY GN N P W...

Page 19: ...rts 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 readi...

Page 20: ...hat the primary interlock switch the secondary interlock 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 H DISASSEMBLING DOOR Figure 17 1 Remove the dielectric choke by using knife blade or small screw driver etc ...

Page 21: ...ssembly 2 Remove top cabinet bolts while supporting unit 3 Lift off back hooks and pull unit forward slowly providing adequate support to prevent dropping unit during removal 4 Remove MOUNT ALL loosening one screw loosening one screw securing the ventilation Motor and back plate See Figure 19 a 5 Carefully pull the ventilation motor ASS Y out of the microwave oven See Figure 19 b K REPLACING THE H...

Page 22: ...oid scratching the cavity M REMOVING CONVECTION HEATER THERMISTOR AND DAMPER MOTOR Figure 23 1 Remove the outer case 2 Remove the air duct by removing six screws securing it to the oven front plate guide air and glasswool L cover 3 Disconnect the wire leads of air duct 4 Remove the magnetron 5 Remove the latch board assembly 6 Remove the bottom plate by removing four screws 7 Remove the four net s...

Page 23: ...ent 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 THE LATCH AND SWITCH CLOSING 3 Loos...

Page 24: ... the body of the switches in the following sequence Interlock Monitor Switch Secondary Interlock Switch Primary 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 proper seq...

Page 25: ...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 closed meter shoul...

Page 26: ...SFORMER Wire leads are removed 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 meter scale Rx1000 Filament to chassis 1 Remove wire leads 2 Measure resistance ohm meter scale Rx1 Primary winding Secondary winding to ground Filament winding 3 Measure re...

Page 27: ... Measure continuity Reverse ohm meter scale Rx1000 1 Remove wire leads 2 Measure resistance ohm meter scale Rx1 Normal Momentarily indicates several ohm and then gradually returns to infinite Normal Infinite Normal Continuity Abnormal Infinite Normal Infinite Abnormal Continuity Normal readings Resistance Approx 6 to 13 ohm Current Approx 13A Abnormal Infinite or several Ohm meter Figure 25 a Ohm ...

Page 28: ...are properly engaged with hooks on the plastic fastener MATRIX CIRCUIT FOR TOUCH KEY BOARD CONNECTOR KEY CON 1 Remove the 3 pin connector from PCB 2 Measure resistance across pins 1 2 3 Across pins 2 3 ohm meter scale Rx1 Normal Approximately at 68 35 F Abnormal Infinite or several FPC CONNECTOR Top Resistance value When touched Less than 400 ohms When not touched More than 1 mega ohm 1 2 3 Figure...

Page 29: ...wire leads 2 Measure resistance ohm meter scale Rx1000 1 Remove the connector from PCB 2 Measure resistance across pins 1 3 ohm meter scale Rx1 Normal Approximately ohm Abnormal Infinite or several Normal Approximately Abnormal Infinite or several Normal Approximately 250 to 350 Kohm at 68 35 F Abnormal Infinite or several F M 35 55 ohm C M 20 35 ohm High Black Blue Medium White Blue Slow Gray Blu...

Page 30: ...or the interlock monitor switches are adjusted or replaced 7 19 COMPONENTS TEST PROCEDURES RESULTS RELAY 2 RELAY 11 1 Measure continuity ohm meter scale Rx1 2 Remove the lead wires and operate oven at power level 1 through power level 10 1 Measure continuity ohm meter scale Rx1 2 Remove the lead wires and operate oven at Convection Cooking POWER LEVEL 1 2 3 4 5 6 7 8 9 10 4 sec 6 sec 8 sec 10 sec ...

Page 31: ...the door is closed Remove the mate connector of I O CON from the circuit board Does the unit still operate Replace the circuit board Replace RELAY1 NO NO YES YES GOOD Defective RELAY1 PROBLEM B FAN motor and oven lamp turn on When the door is closed and START key is touched Replace the circuit board YES NO GOOD ...

Page 32: ...l xfmr Oven circuit NO All normal except MW power Not normal High volt Section Repair or Replace 3 CHECKOUT PROCEDURES FOR CIRCUIT BOARD The following symptoms indicate a defective circuit board 1 The start function fails to operate but the high voltage Systems the interlock switches the door sensing and the relay check good 2 The unit with a normal relay continuously operates 3 Proper temperature...

Page 33: ...st bake cook 225 F use dial Press start Press Fast Bake Actual oven temperature will be displayed Display PREHEAT OFFSET ON Ready beep Cycle 225 F Press Convection Bake Actual oven temperature will be displayed Combination Cook YES Control system normal YES Replace thermistor NO Control system normal YES Replace smart board NO Control system normal YES Replace thermistor NO Control system normal Y...

Page 34: ... system normal YES Replace Damper motor NO Control system normal YES Replace smart board NO Convection Cook Remove neon light Program bake cook 225 F use dial Press start Display PREHEAT OFFSET ON Ready beep Cycle 225 F Open the door Dampe is closed Control system normal YES Replace Damper Motor NO Control system normal YES Replace smart board NO ...

Page 35: ...n o c f o 3 n i p d n a s n u R s n u R 0 0 2 1 0 0 2 1 V 0 2 1 e c a l p e R d r a o b t i u c r i c l a m r o N d r a o b t i u c r i c l a m r o N e c n a t s i s e r e g a t l o V t c e r r o c n i t c e r r o C s n o i t c e n n o c s n u R s n u R s n u R h c u o t f o e c n a t s i s e r e r u s a e M g n i v o m e r r e t f a d r a o b y e k 1 S r o t c e n n o c 7 1 7 d n a 4 7 e g a p e ...

Page 36: ... R s n u R s n u R n a f f o n o i t a r e p o k c e h C y e k T R A T S n e h w r o t o m d e h c u o t s i e c n a t s i s e r e r u s a e M r o t i c a p a c V H f o 6 1 7 e g a p e e s e c n a t s i s e R t c e r r o c n i e c n a t s i s e r e r u s a e M r o t o m n a f f o m h o 0 6 o t 0 3 C A l a n i m r e T m h o 0 2 o t 0 1 B A l a n i m r e T e c n a t s i s e R t c e r r o c n i e c a...

Page 37: ... t n o c k c e h C r o t c e n n o c f o t c a t n o c e h t k c e h C 8 1 7 e g a p e e s 1 1 2 y a l e r e c n a t s i s e R t c e r r o c n i f o y t i u n i t n o c e h t k c e h C 6 1 7 e g a p e e s C V H T V H l a m r o N e c n a t s i s e R t c e r r o c n i C V H l a m r o N l a m r o n b A D V H e c a l p e R l a m r o N n o r t e n g a M e c a l p e R n o r t e n g a M l a m r o N l a m...

Page 38: ... F No buzzing when touching the key between stages or at end of cooking 1 l a m r o N d r a o b t i u c r i c l a m r o n k c e h C n o i t a r e p o d r a o b t i u c r i c e c a l p e R d r a o b t i u c r i c s n u R ...

Page 39: ...u c r i c K O t c a t n o C l a m r o N t c a t n o c t c e r r o C g n i t a e s t c a t n o c k c e h C r o t c e n n o c f o 4 7 e g a p e e s s n u R e c a l p e R n o i t a l i t n e v Y S S A r o t o m s n u r O N l a m r o N n o i t a l i t n e v Y S S A r o t o m f o t c a t n o c e h t k c e h C l a m r e h t n o r t e n g a m t a t s o m r e h t n e v o d n a e s u f s n u R s n u R t c ...

Page 40: ...3581A 9383EA 13551A 13551A 13213A WTP004 WTP004 13213A 13552A 13552A 14026A 14026A 13651A 14970A WTT028 136502 136501 14970A WSZ131 WWS016 WWS016 EXPLODED VIEW DOOR PARTS FOR MODEL JVM1790BK JVM1790CK JVM1790WK FOR MODEL JVM1790SK ...

Page 41: ...23551A 23551A WTP013 WTP015 WTP013 24810P 23506A 24810P 268711 268711 249401 WTT029 WTT027 WTT027 249401 For Model JVM1790BK For Model JVM1790WK JVM1790CK CONTROLLER PARTS FOR MODEL JVM1790BK JVM1790CK JVM1790WK FOR MODEL JVM1790SK ...

Page 42: ... WTT029 WTT027 33550P 36549S 34890C 36912C 33112U 33809A 53035B 63303A 34931A 34930R 33740B 33530A 34960A WTT029 WTT027 For Model JVM1790WK JVM1790CK For Model JVM1790BK JVM1790SK WTT020 WTT022 For Model JVM1790WK JVM1790CK For Model JVM1790BK JVM1790SK WTT020 WTT022 For Model JVM1790BK JVM1790SK For Model JVM1790WK JVM1790CK WTT029 WTT027 33740A OVEN CAVITY PARTS ...

Page 43: ... 8 4 EV WSZ084 43500A 43501A 466001 466003 466001 44510A LATCH BOARD PARTS ...

Page 44: ...6208A 56549F 55238A 55013L 55300S 55900C WNH003 WWS005 34370T 35889A 56851D 34930W 56324A 56549B 55012A 466002 548102 54810S 36549R 36549C 56322A 53551S WTT022 WSZ002 WTP013 WTP004 WTP013 WTP013 WSZ002 WNH002 53300B 50CZZH 54810C 53504A 549801 56170D 569302 569301 56930V WTT011 WSZ002 WNH002 WTP013 569301 55893A INTERIOR PARTS I ...

Page 45: ...1A004A 4931W1A009E Discord original for parts supplied Change pieces simultaneously After Before WTP004 WTT030 WTT028 WTT028 WTT028 352641 56930G 352642 55262A 56501A 50CZZM 56411A 55013U 568771 50FZZA 56201A WTP018 WSZ002 WSZ002 WTT028 WTT028 WTP004 WTT028 36549V INTERIOR PARTS II ...

Page 46: ... 8 7 EV 01 USE CARE 06 1 06 2 WALL TEMPLATE UPPER TEMPLATE 07 MINI MANUAL 04 INSTALLATION MANUAL VINYL BAG 63300M 65862B WTT028 63861A 65862D INSTALLATION PARTS ...

Page 47: ...10 1 SCHEMATIC DIAGRAM OF P C B ...

Page 48: ...10 2 PRINTED CIRCUIT BOARD ...

Page 49: ...Printed in Korea P NO 3828W5S4595 ...

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