R-408JK R- 408JW SERVICE MANUAL S24M231R408JE MICROWAVE OVENS MODELS R-408JK R-408JW R-408JW In the interest of user-safety the oven should be restored to its original condition and only parts identical to those specified should be used. WARNING TO SERVICE PERSONNEL: Microwave ovens contain circuitry capable of producing very high voltage and current, contact with following parts may result in a severe, possibly fatal, electrical shock.
R- 408JK R-408JW PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY (a) Do not operate or allow the oven to be operated with the door open.
R-408JK R-408JW WARNING TO SERVICE PERSONNEL Microwave ovens contain circuitry capable of producing very high voltage and current, contact with following parts may result in a severe, possibly fatal, electrical shock. (Example) High Voltage Capacitor, High Voltage Power Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage Harness etc.. Read the Service Manual carefully and follow all instructions. Don't Touch ! Danger High Voltage When the testing is completed, 1.
R-408JK R-408JW MICROWAVE MEASUREMENT PROCEDURE A. Requirements: 1) Microwave leakage limit (Power density limit): The power density of microwave radiation emitted by a microwave oven should not exceed 1mW/cm2 at any point 5cm or more from the external surface of the oven, measured prior to acquisition by a purchaser, and thereafter (through the useful life of the oven), 5 mW/cm2 at any point 5cm or more from the external surface of the oven.
R-408JK R-408JW SERVICE MANUAL PRODUCT DESCRIPTION MICROWAVE OVEN R-408JK/R-408JW GENERAL INFORMATION FOREWORD This Manual has been prepared to provide Sharp Electronics Corp. Service Personnel with Operation and Service Information for the SHARP MICROWAVE OVENS R-408JK and R-408JW. It is recommended that service personnel carefully study the entire text of this manual so that they will be qualified to render satisfactory customer service.
R-408JK R-408JW SPECIFICATION ITEM DESCRIPTION PowerRequirements 120 Volts 14.3 Amperes, 1700 watts 60 Hertz Single phase, 3 wire grounded Power Output 1200 watts (IEC TEST PROCEDURE) Operating frequency of 2450MHz Case Dimensions Width 21-21/32" Height 12-3/8" Depth 18-7/16" Cooking Cavity Dimensions Width 15-23/32" Height 9-21/32" Depth 17-7/8" 1.6 Cubic Feet Control Complement Touch Control System Clock ( 1:00 - 12:59 ) Timer (0 - 99 min.
R-408JK R-408JW a qualified electrician and have it replaced with a properly grounded three-pronged wall receptacle or have a grounding adapter properly grounded and polarized. If the extension cord must be used, it should be a 3-wire, 15 amp. or higher rated cord. Do not drape over a countertop or table where it can be pulled on by children or tripped over accidentally. Grounded Receptacle Box 3-Pronged Plug CAUTION: DO NOT UNDER ANY CIRCUMSTANCES CUT OR REMOVE THE ROUND GROUNDING PRONG FROM THIS PLUG.
R-408JK R-408JW OPERATION DESCRIPTION OF OPERATING SEQUENCE The following is a description of component functions during oven operation. and is mechanically associated with the door so that it will function in the following sequence. (1) When the door opens from the closed position, the secondary interlock relay (RY2) and primary interlock switch open their contacts. And contacts of the relay (RY1) remains closed. Then the monitor switch contacts close.
R-408JK R-408JW Note:* Indicates component SCHEMATIC NOTE: CONDITION OF OVEN 1. Door Closed 2. CLOCK APPEARS ON DISPLAY C AV IT Y T E MP E R AT UR E F US E C /T F US E OR G OR G BR N OR G RED RED N.O. C OM. B2 GR N RED MAG NE T R ON (R Y 1) C ONT R OL UNIT C OM. HIG H VOLTAG E C APAC ITOR F1 BR N OR G OL OV E N LAMP MONITOR S WIT C H N.C . T UR N T T M TAB LE F M FAN MOTOR MOTOR HIG H VOLTAG E R E C T IF IE R C OM. WHT WHT WHT GRY OR G OR G OV E N LAMP R E LAY WHT WHT N.O.
R-408JK R-408JW DESCRIPTION AND FUNCTION OF COMPONENTS DOOR OPEN MECHANISM 3. If the door is opened, and the secondary interlock relay (RY2) and primary interlock switch contacts fail to open, the C/T fuse blows simultaneously with closing of the monitor switch contacts. CAUTION: BEFORE REPLACING A BLOWN C/T FUSE TEST THE DOOR SENSING SWITCH, SECONDARY INTERLOCK RELAY (RY2), RELAY (RY1), PRIMARY INTERLOCK SWITCH AND MONITOR SWITCH FOR PROPER OPERATION. (REFER TO CHAPTER "TEST PROCEDURE").
R-408JK R-408JW TROUBLESHOOTING GUIDE Never touch any part in the circuit with your hand or an uninsulated tool while the power supply is connected. When troubleshooting the microwave oven, it is helpful to follow the Sequence of Operation in performing the checks. Many of the possible causes of trouble will require that a specific test be performed. These tests are given a procedure letter which will be found in the "Test Procedure "section.
R-408JK R-408JW CK = Check / RE = Replace Home fuse or circuit breaker blows when power cord is plugged into wall receptacle C/T fuse blows when power cord is plugged into wall receptacle. OFF CONDITION All letters and indicators do not appear in display when power cord is first plugged into wall outlet. Display does not operate properly when STOP/CLEAR key is touched. (Buzzer should sound and ":" or time of day should appear in display.) Oven lamp does not light when door is opened.
R-408JK R-408JW TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 4. To test for an open filament, isolate the magnetron from the high voltage circuit. A continuity check across the magnetron filament leads should indicate less than 1 ohm. 5. To test for a shorted magnetron, connect the ohmmeter leads between the magnetron filament leads and chassis ground. This test should indicate an infinite resistance. If there is little or no resistance the magnetron is grounded and must be replaced. 6.
R-408JK R-408JW TEST PROCEDURES PROCEDURE LETTER C COMPONENT TEST HIGH VOLTAGE RECTIFIER TEST 1. 2. 3. 4. Disconnect the power supply cord, and then remove outer case. Open the door and block it open. Discharge high voltage capacitor. Isolate the rectifier from the circuit. Using the highest ohm scale of the meter, read the resistance across the terminals and observe, reverse the leads to the rectifier terminals and observe meter reading.
R-408JK R-408JW TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 5. If the C/T fuse is blown when the door is opened, check the secondary interlock relay, primary interlock switch and monitor switch according to the "TEST PROCEDURE" for those switches before replacing the blown monitor fuse. CAUTION: BEFORE REPLACING A BLOWN C/T FUSE, TEST THE SECONDARY INTERLOCK RELAY, PRIMARY INTERLOCK SWITCH, DOOR SENSING SWITCH AND MONITOR SWITCH FOR PROPER OPERATION.
R-408JK R-408JW TEST PROCEDURES PROCEDURE LETTER G MONITOR SWITCH TEST 1. 2. 3. 4. 5. 6. 7. 8. COMPONENT TEST Disconnect the power supply cord, and then remove outer case. Open the door and block it open. Discharge high voltage capacitor. Before performing this test, make sure that the primary interlock switch and the secondary interlock relay are operating properly, according to the above Switch Test Procedure. Disconnect the wire lead from the monitor switch (COM) terminal.
R-408JK R-408JW TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 2. Control Unit The following symptoms indicate a defective control unit. 2-1 In connection with pads. a) When touching the pads, a certain group of pads do not produce a signal. b) When touching the pads, no pads produce a signal. 2-2 In connection with indicators a) At a certain digit, all or some segments do not light up. b) At a certain digit, brightness is low. c) Only one indicator does not light.
R-408JK R-408JW TEST PROCEDURES PROCEDURE LETTER G5 G4 G3 G2 G1 G9 5 3 8 1 0 4 9 2 G10 G8 G7 COMPONENT TEST G6 7 6 Pin NO. G1 Key unit ribbon cable G11 HOT KEEP NIGHT FRESH POPCORN WATER WARM VEGETABLES LIGHT TIMER BAKED GROUND POWER SOFTEN REHEAT RICE MEAT CLOCK POTATOES LEVEL STOP FROZEN START FROZEN WARM MINUTE PLUS VEGETABLES ENTREES CLEAR G13 G12 MELT Pin NO. G13 DEFROST Key unit (Membrane Switch) front view Key Unit K RELAY TEST 1.
R-408JK R-408JW TEST PROCEDURES PROCEDURE LETTER M COMPONENT TEST FOIL PATTERN ON THE PRINTED WIRING BOARD TEST To protect the electronic circuits, this model is provided with a fine foil pattern added to the primary on the PWB, this foil pattern acts as a fuse. 1. Foil pattern check and repairs. 1) Disconnect the power supply cord, and then remove outer case. 2) Open the door and block it open. 3) Discharge high voltage capacitor. 4) Follow the troubleshooting guide given below for repair.
R-408JK R-408JW TOUCH CONTROL PANEL ASSEMBLY OUTLINE OF TOUCH CONTROL PANEL The touch control section consists of the following units. (1) Key Unit (2) Control Unit (The Control Unit consists of Power Unit and LSI Unit). 3) Power Source Circuit This circuit generates voltages necessary in the control unit from the AC line voltage. In addition, the synchronizing signal is available in order to compose a basic standard time in the clock circuit.
R-408JK R-408JW DESCRIPTION OF LSI LSI The I/O signal of the LSI is detailed in the following table. Pin No. Signal I/O Description 1-2 VL2-VL1 IN Power source voltage input terminal. Standard voltage for LCD. 3-6 AN7-AN4 IN Terminal to change cooking input according to the Model. By using the A/D converter contained in the LSI, DC voltage in accordance with the Model in operation is applied to set up its cooking constant. 7 AN3 IN Signal coming from touch key.
R-408JK R-408JW Pin No. Signal I/O 25 P41 IN Signal similar to AN3. When either G11 line on key matrix is touched, a corresponding signal will be input into P41. 26 P40 IN Connected to GND through the pull-down resistor. 27 RESET IN Auto clear terminal. Signal is input to reset the LSI to the initial state when power is applied. 28 P71 IN Signal similar to AN3. When either G10 line on key matrix is touched, a corresponding signal will be input into P71.
R-408JK R-408JW Pin No. Signal I/O Description Connected to LCD. The relation between signals are as follows: LSI signal (Pin No.) LCD (Pin No.) SEG0 (72) ................................ SEG 0 SEG1 (71) ................................ SEG 1 SEG2 (70) ................................ SEG 2 SEG3 (69) ................................ SEG 3 SEG4 (68) ................................ SEG 4 SEG5 (67) ................................ SEG 5 SEG6 (66) ................................ SEG 6 SEG7 (65) .........
R-408JK R-408JW TOUCH CONTROL PANEL SERVICING 1. Precautions for Handling Electronic Components This unit uses CMOS LSI in the integral part of the circuits. When handling these parts, the following precautions should be strictly followed. CMOS LSI have extremely high impedance at its input and output terminals. For this reason, it is easily influenced by the surrounding high voltage power source, static electricity charge in clothes, etc.
R-408JK R-408JW COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE WARNING AGAINST HIGH VOLTAGE: Microwave ovens contain circuitry capable of producing very high voltage and current. Contact with the following parts may result in severe, possibly fatal, electric shock. (Example) High Voltage Capacitor, Power Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage Harness etc.. WARNING: To Avoid possible exposure to microwave energy, please follow the instructions below before operating the oven.
R-408JK R-408JW CAUTION: 1. DISCONNECT OVEN FROM POWER SUPPLY BEFORE REMOVING OUTER CASE. 2. DISCHARGE THE HIGH VOLTAGE CAPACITOR BEFORE TOUCHING ANY OVEN COMPONENTS OR WIRING. NOTE: When replacing the outer case, the 2 special Torx screws must be reinstalled in the same locations. Special screw Screw Driver (Type: TORX T20 H or GTXH20-100) POWER TRANSFORMER REMOVAL Re-install 1. Rest transformer on the bottom plate with its primary terminals toward the oven face plate. 2.
R-408JK R-408JW OVEN LAMP AND LAMP SOCKET REMOVAL 1. 2. 3. 4. 5. Disconnect the power supply cord and remove outer case. Open the door and block it open. Discharge high voltage capacitor. Remove the oven lamp from the oven lamp socket. Pull the wire leads from the oven lamp socket by pushing the terminal hole of the oven lamp socket with the small flat type screw driver. 6. Remove the oven lamp socket from the magnetron duct by turning the socket counterclockwise. 7.
R-408JK R-408JW Installation 1. Remove remaining adhesive on the control panel frame surfaces with a soft cloth soaked in alcohol. 2. Make sure that the LCD sheet and the liquid crystal display is installed in position. 3. Remove the backing paper from the new membrane switch and ribbon cable. 4. Insert the ribbon cable of the membrane switch into the slit of the control panel frame. 5.
R-408JK R-408JW COOLING FAN MOTOR REMOVAL REMOVAL 1. Disconnect the power supply cord and then remove outer case. 2. Open the door and block it open. 3. Discharge high voltage capacitor. 4. Disconnect the wire leads from the fan motor. 5. Remove the two (2) screws holding the fan motor to the oven cavity back plate. 6. Remove the fan blade from the fan motor shaft according to the following procedure. 7. Hold the edge of the rotor of the fan motor by using a pair of groove joint pliers.
R-408JK R-408JW 3. Secure latch hook (with two (2) mounting screws) to oven flange. 4. Make sure that the monitor switch is operating properly and check continuity of the monitor circuit. Refer to chapter "Test Procedure" and Adjustment procedure. DOORSENSINGSWITCH/PRIMARY INTERLOCKSWITCHANDMONITORSWITCHADJUSTMENT 1. Disconnect the power supply cord, and then remove outer case. 2. Open the door and block it open. 3. Discharge high voltage capacitor.
R-408JK R-408JW 9. Release the door panel from twelve (12) tabs of door frame. 10.Remove the door panel from the door frame. 11.Now, door panel with sealer film is free. 12.Tear sealer film from door panel. 13.Now, door panel is free. 14.Slide latch head upward and remove it from door frame with releasing latch spring from door frame and latch head. 15.Now, latch head and latch spring are free. 16.Remove door screen from door frame 17.Now, door frame is free. RE-INSTALL 1.
1 2 COM. RY2 N.O. 2 N.O. COM. G SECONDARY INTERLOCK RELAY T1 3 30 4 COM. 5 GRY COM. PRIMARY NO INTERLOCK SWITCH WHT WHT WHT WHT TURNTABLE MOTOR Figure S-1. Pictorial Diagram C/T FUSE BRN RED WHT WHT ORG FAN MOTOR MAGNETRON POWER TRANSFORMER H.V. RECTIFIER HIGH VOLTAGE WIRE A HIGH VOLTAGE CAPACITOR HIGH VOLTAGE COMPONENTS NOTE: Hot (ORG) wire must be connected to the terminal with blue mark on the oven light socket. BLUE MARK ORG WHT 4 GRY WHT E MONITOR SWITCH N.C.
R-408JK R-408JW 1 2 4 3 5 6 A B B C C Figure S-3.
R-408JK R-408JW 1 2 4 3 5 6 A A B B DIP CHIP SIDE C C J3 CN-F C10 R90 C4 1 2 3 LED D31 CN-B D D R3 R5 C5 R6 D8 WH-2 B1 2 E Q1 Q4 SP1 Q3 DZ1 E C B E C B J1 E Q2 E C B D30 2 1 J5 J6 2 1 WH-2 D5 T1 J2 R4 E D6 R2 R7 RY2 C1 R8 F F D1 D2 P S L1 D3 D4 VRS1 G G C2 D7 RY1 H H Figure S-5 .
R-408JK R-408JW PARTS LIST ∆” may cause undue microwave exposure. Note: The parts marked “∆ The parts marked “*” are used in voltage more than 250V. "§" MARK: PARTS DELIVERY SECTION. REF. NO. PART NO.
R-408JK R-408JW REF. NO. PART NO.
R-408JK R-408JW 2 1 4 3 6 5 OVEN AND CABINET PARTS 7-4 A A 7-4 7-7 2-3 B B 4-7 7-7 6-5 7-5 1-7 C C 1-4 4-6 7-3 7-6 1-11 D D 1-5 4-8 7-6 4-2 7-4 E 1-8 4-9 6-4 E 7-4 7-2 7-2 6-3 1-3 7-4 7-1 1-6 4-3 4-10 4-5 1-9 1-10 F 7-5 2-1 6-2 F 1-5 1-6 7-1 4-4 4-1 1-1 1-2 G G 7-4 7-4 2-2 2-2 7-4 2-2 4-11 2-2 H H 1 2 4 3 35 5 6
R-408JK R-408JW 2 1 4 3 6 5 CONTROL PANEL PARTS 3-2 A A 3-13 3-1 3-10 3-11 3-9 3-12 3-3 3-6 3-8 3-7 B B 3-5 3-4 C C DOOR PARTS 5-7 5-6 D D 5-4 E E 5-8 5-5 5-9 F F 5-2 MISCELLANEOUS 5-3 G G 5-1 6-1 6-7 H 1 2 4 3 36 Actual wire harness may be different from illustration.
R-408JK R-408JW PACKING AND ACCESSORIES TOP PAD ASSEMBLY DOOR PROTECTION SHEET 6-3 TURNTABLE TRAY PLASTIC BAG ON TOP OF THE OVEN TRAY HOLDER 6-6 OPERATION MANUAL IN TO TH EO NC VE AV ITY BOTTOM PAD ASSEMBLY 6-2 TURNTABLE SUPPORT PACKING CASE Non-replaceable items 37
R-408JK R-408JW COPYRIGHT © 2004 BY SHARP CORPORATION ALL RIGHTS RESERVED. No part of this publication may be reproduced, stored in retrieval systems, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of the publisher. 2004 SHARP CORP. (4M2.00E) Printed in U.S.
