SHARP R408CW, R-409CK Service Manual

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R-408CW R-409CK

SHARP@

R-408CW

SERVICE MANUAL

S39M125R408CE

MICROWAVE OVEN MODELS

R-408CW/R=409CK

In the interest of user-safety the oven is to be restored to its original condition and only the 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 the following parts may result in a severe, possibly fatal electrical shock.(High Voltage Capacitor,

High Voltage Power Transformer, Magnetron,

High Voltage Rectifier Assembly, High Voltage

Harness etc..)

SECTION

PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICE TO AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY.

Before Servicing .............................................................

Forewordandwarning

Warning to Service Personnel

Specifications ...............................................................................

Generalinformation KeyUnitLayout

Operation ..................................................................................

Servicing and Troubleshooting Guide

TestProcedures..........................................................................~

Touch Control Outline Component Replacement and Adjustment Procedure Microwave Measurement Procedure Wiring/Schematic Diagram

Parts .....................................................................................

Packing and Accessories

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SHARP ELECTRONICS CORPORATION

Service Headquarters: Sharp Plaza, Mahwah, New Jersey, 07430-2135

...........

PAGE

Inside Front Cover Inside Front Cover

1 2 3 4 5 6 8

. 10

18 23 29 30 35 39

Do not operate or allow the oven to be operated with the door open.

( )

Make the following safety checks on all ovens to be serviced before activating the magnetron

(b)

or other microwave source, and make repairs as necessary: (1) Interlock operation, (2) proper door closing, (3) seal and sealing surfaces (arcing, wear, and other damage), (4) damage to or loosening of hinges and latches, (5) evidence of dropping or abuse.

Before turning on microwave power for any service test or inspection within the microwave gen-

()

erating compartments, check the magnetron, waveguide or transmission line, and cavity for proper alignment, integrity, and connections.

Any defective or misadjusted components in the interlock, monitor, door seal, and microwave

(d)

generation and transmission systems shall be repaired, replaced, or adjusted by procedures described in this manual before the oven is released to the owner.

A microwave leakage check to verify compliance with the Federal Performance Standard

()

should be performed on each oven prior to releasing oven to the owner.

(RD21101U)

Before servicing an operative unit, perform a microwave emission check as per the Microwave Measurement Procedure outlined in this service manual. If microwave emissions level is in excess of the specified limit, contact SHARP ELECTRONICS CORPORATION immediately @

I-800-237-4277.

If the unit operates with the door open, service person should 1) tell the user not to operate the oven and 2) contact SHARP ELECTRONICS CORPORATION and DHHS immediately.

Service personnel should inform SHARP ELECTRONICS CORPORATION of any certified unit found with emissions in excess of 4mW/cm2. The owner of the unit should be instructed not to use the unit until the oven has been brought into compliance.

(RD81001 U)

SERVICE MANUAL

SHARR

Microwave Ovens R=408CW/R=409CK

Foreword

This manual has been prepared to provide Sharp

Electronics Corporation personnel with complete operation and service information for Sharp microwave oven models R-408CW/R-409CK.

It is recommended that service personnel carefully study the entire text of this manual so they will be qualified to render satisfactory customer service.

Check interlock switches and the door seal carefully. Special attention must be given to avoid electrical shock and microwave radiation hazards.

WARNING

Never operate the oven until the following points are ensured:

(A)The door is tightly closed. (B)The door brackets and hinges are not defective. (C)The door packing is not damaged. (D)The door is not deformed or warped. (E)There are no other visible signs of damage to the

oven.

DANGER

Certain initial parts are intentionally not grounded and present a risk of electrical shock only during servicing. Service personnel - Do not contact the following parts while the appliance is energized; High Voltage Capacitor, Power Transformer, Magnetron, High Voltage Rectifier Assembly and High voltage Harness. If provided, Vent Hood, Fan Assembly and Cooling Fan motor.

All of the parts marked “*” on parts list are used at voltages more than 25OV.

Removal of the outer case cabinet gives access to voltage above 250V.

All of the parts marked “A” on parts list may cause undue microwave exposure, by themselves, or when they are damaged, loosened or removed.

Specifications

General Information

Key Unit Layout

Operation

Troubleshooting / Test Procedure&

Touch Control Panel

and hdjustmeni

Wiring / Schematic Diagram

Sharp Electronics Corporation

Sharp Plaza

Mahwah, New Jersey 07430-2135

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.

Before Servicing

Don’t Touch ! Danger High Vol

tage

1. Disconnect the power supply cord and then remove outer case cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

WARNING:RlSK OF ELECTRICAL SHOCK. DISCHARGE THE HIGH VOLTAGE CAPACITOR BEFORE SERVICING.

The high-voltage capacitor remains charged about 60 seconds after the oven has been switched off. Wait for 60 seconds and then short-circuit the connection of the high voltage capacitor (that is the connecting lead of the high voltage rectifier) against the chassis with the use of an insulated screwdriver.

Whenever troubleshooting is performed, the power supply must be disconnected. In some cases it may be necessary to connect the power supply after the outer case has been removed, in this event:

Disconnect the power supply cord and then remove

outer case cabinet.

Open the door and block it open.

. 3.

Discharge the high voltage capacitor. Disconnect the leads to the primary of the power

4. transformer.

Ensure that the leads remain isolated from other

components and oven chassis by using insulation tape. After the above procedure, reconnect the power sup-

6. ply cord.

When the testing is completed

1. Disconnect the power supply cord and then remove outer case cabinet.

Open the door and block it open.

Discharge the high voltage capacitor.

Reconnect the leads to the primary of the power

transformer.

Re-install the outer case cabinet.

Reconnect the power supply cord after the outer

case cabinet is installed.

Start the oven and check all functions.

After repairing

1. Reconnect all leads removed from components dur-

ing testing.

2. Re-install the outer case (cabinet).

3. Reconnect the power supply cord after the outer case is installed.

4. Reconnect the power supply cord after the outer case is installed.

5. Run the oven and check all functions.

Microwave ovens should not be operated empty. To test for the presence of microwave energy within a cavity, place a cup of cold water on the oven turntable, close the door and set the power to HIGH and set the microwave timer for two (2) minutes. When the two minutes has elapsed (timer at zero), carefully check to see if the water is hot. If the water remains cold, carry out Before

Servicing procedure and re-examine the connection to

the component being tested. When all service work is completed and the oven is fully

assembled, the microwave power output should be checked and the microwave leakage test should be car-

ried out.

SPECIFICATIONS

Item Description

Power Requirements 120 Volts

13.3 Amperes 1550Watts 60 Hertz Single phase, 3 wire grounded

Power Output 1100 watts (IEC-705 Test Procedure)

Operating frequency of 2450 MHz

Case Dimensions Width 2111/,$

Height 123/<’ (including feet) Depth 173/i’

R-408CW R-409CK

Cooking Cavity

1.4 Cu.Ft.

Control Complement Touch Control System

Width 15” Height 97/,;’ Depth 1631:’ Tray Size 141/< Diameter

Clock (I:00 - 12:59) Timer (0 - 99 min. 99 sec.) Microwave Power for variable cooking

Repetition Rate;

P-HI (HIGH) . . . . . . . . .

P-90 . . , . . . . . . . . . . . . . . approx. 90% of full power

P-80 . . . . . . . . . . . . . . . . .

P-70 (MED HIGH) . . . .

P-60 . . . . . . . . . . . . . . . . .

P-50 (MED) . . . . . . . . . .

P-40 . . . . . . . . . . . . . . . . .

P-30 (MED LOW) . . . . .

P-20 . . . . . . . . . . . . . . . . .

P-IO . . . . . . . . . . . . . . . . .

P-O...................

FEATURES

Instant Action Compu Defrost(3) Minute Plus Timer/Clock Popcorn Variable Power (10) 4 Stage Cooking

Full power throughout the cooking time approx. 80% of full power

approx. 70% of full power approx. 60% of full power approx. 50% of full power approx. 40% of full power approx. 30% of full power approx. 20% of full power approx. 10% of full power No power throughout the cooking time

Oven Cavity Light Safety Standard

Yes

UL Listed FCC Authorized DHHS Rules, CFR, Title 21, Chapter 1, Subchapter J

Grounding Instructions

This oven must be fully grounded at all times. This appliance must be connected to a 120 volt, 60 Hz, AC only, 15 Ampere or more fused electrical supply. It is recommended that a separate circuit serving only this appliance be provided. When installing this appliance, observe all applicable codes and ordinances.

WARNING: Improper use of the grounding plug can result in a risk of electric shock.

Where a two-pronged wall-receptacle is encountered, it is the personal responsibility and obligation of the customer to contact a qualified electrician and have it replaced with a properly polarized and grounded threepronged wall receptacle or use a grounding adaptor. If an extension cord must be used, it should be a 3=wire,

15 ampere minimum cord.

Grounded Grounded Receptacle Box

3 Pronged Plug

Grounding Pin

Receptacle

3 Pronged Receptacle

Receptacle Box

Grounding Screw

Do not under any circumstances cut or remove the round grounding prong from this plug.

Oven

Diagram

1. Digital display

2. Auto-Touch control panel

3. Door open button

4. Door latches

5. Removable turntable support

6. Removable turntable

7. Oven lamp

8. Oven door with see through window

9. Waveguide cover

10. Power Cord

Key Unit Layout

MINUTE PLUS

INSTANT ACTION

TO ADJUST QUANTITY -TOUCH PAD AGAIN

1 Ground Meat 2 Steaks/Chops 3 Chicken Pieces

Power

Level

R-408CW

COMPU DEFROST

* I

5 1 8

1 Timer

6 9

Clock

3 Chicken Pieces

f11213’

I I

I 5 I 6

I I

stop

Clear

( START j

R-409CK

R-408CW

R-409CK

Description of Operating Sequence

The following is a description of component functions during oven operation:

Off Condition

Closing the door activates the door sensing switch and secondary interlock switch. In this condition, the monitor switch contacts are opened. When the oven is plugged in, 120 volts AC is supplied to the control unit (see schematic diagram). The display flashes 88:88. To set any program or set the clock, first touch the STOP/ CLEAR pad. The display clears and “ : ” appears and the control unit counts every minute.

Cooking Condition

Program desired cooking time and Variable Cooking Control by touching the NUMBER pads and the Power Level pad of the Variable Cooking Control. When START is touched, the following operations occur:

The relay contacts are closed and components connected to the relays (RY-1 and RY-2) are turned on. (For details, see table below.)

Relay

RY-1 Oven Lamp/Turntable Motor/Fan Motor RY-2

120 volts AC is supplied to the primary winding of the

2. power transformer and is converted to approximately 3.3 volts AC on the filament winding and approximately 2370 volts AC on the high voltage winding.

The filament winding voltage heats the magnetron

3. filament and the high voltage is sent to a voltage doubler circuit.

The microwave energy produced by the magnetron is channeled through the waveguide into the cavity feed-box and into the cavity where the food is cooked.

Upon completion of the cooking cycle, the power transformer, oven lamp and cooling fan are turned off and the generation of microwave energy is terminated.

When the door is opened during a cook cycle, the

6. monitor switch, door sensing switch, secondary interlock switch and primary interlock relay are activated with the following results. The turntable motor, cooling fan motor and the high voltage components are de-energized. The oven lamp remains on and the digital readout displays the time still remaining in the cook cycle when the door was opened.

The monitor switch is electrically monitoring the op-

7. eration of the secondary interlock switch and primary

Components

Power Transformer

OPERATION

interlock relay and is mechanically associated with

the door so that it functions as follows:

( )

(b)

If the secondary interlock switch and the primary inter-

lock relay contacts are closed when the door is opened, the monitor switch contacts form a short circuit through the monitor fuse, secondary interlock switch and prima-

ry interlock relay causing the monitor fuse to blow.

Power Level P-O to P-90 Cooking

When Variable Cooking Power is programmed, 120 volts AC is supplied to the power transformer intermittently through the contacts of relay RY-2 which is oper-

ated by the control unit within a 32 second time base. Mi-

crowave power operation is as follows:

1 Vari-Mode 1 On Time

P - HI (HIGH) (100% power) 32 sec.

P - 90 (approx. 90% power) 30 sec.

P - 80 (approx. 80% power)

P - 70 (MED, HIGH) (approx. 70% power) 24 sec.

P - 60 (approx. 60% power)

P - 50 (MED) (approx. 50% power) 18 sec.

P - 40 (approx. 40% power) 16 sec.

P - 30 (MED, LOW) (approx. 30 % power)

P - 20 (approx. 20% power)

P-IO (approx. 10% power)

P-O (0% power)

The ON/OFF time ratio does not correspond with the percentage of microwave power, because approximate-

ly 2 seconds are needed for heating the magnetron fila-

ment.

When the door opens from a closed position, the

secondary interlock switch and primary interlock relay open their contacts, then the monitor switch contacts close.

When the door is closed from the open position, the monitor switch contacts first open and the

contacts of the secondary interlock switch close.

IOff Time 1

0 sec.

2 sec.

26 sec. 6 sec.

8 sec.

22 sec.

12 sec.

8 sec.

6 sec.

0 sec.

IO sec.

14 sec.

16 sec.

sec.

24 sec.

26 sec.

32 sec.

DESCRIPTION AND FUNCTION OF COMPONENTS

Cooling Fan Motor

The cooling fan motor drives a blade which draws external cool air. This cool air is directed through the air vanes surrounding the magnetron to cool the magnetron. This air is channeled through the oven cavity to remove steam and vapors given off from the heating foods. It is then exhausted through exhaust vents in the oven cavity.

Oven Temperature Fuse

The oven temperature fuse located on the top of the oven cavity is designed to prevent damage to the unit if the foods in the oven catch fire due to over heating produced by improper setting of cook time or failure of control unit.

Under normal operation, the oven temperature fuse re-

mains closed. However, when abnormally high temperatures are reached within the oven cavity, the fuse will open at 150°C, causing the oven to shut down.

Note: This is a fuse and it does not reset.

Magnetron Temperature Fuse

The magnetron temperature fuse located on top of the

magnetron duct is designed to prevent damage to the

magnetron if an over heated condition develops in the tube due to cooling fan failure, obstructed air ducts, dirty

or blocked air intake, etc.

Under normal operation, the magnetron temperature

fuse remains closed. However, when abnormally high

temperatures are reached within the magnetron the

fuse will open at 1 50°C, causing the oven to shut down.

Note: This is a fuse and it does not reset.

Monitor Switch

The monitor switch is activated (the contacts opened) by the latch head on the door while the door is closed. The

switch is intended to render the oven inoperative by means of blowing the monitor fuse when the contacts of

the primary interlock relay and secondary interlock

switch fail to open when the door is opened.

Monitor Switch Functions

When the door is opened, the monitor switch contacts close (to the ON condition) due to their being normally closed. At this time the primary interlock relay and secondary interlock switch are in the OFF condition (contacts open) due to their being normally open contacts.

When the door is closed, the monitor switch contacts are first opened and then the door sensing switch and the secondary interlock switch contacts close.

Note: When opening the door, each of these

switches operate inversely.

If the door is opened and the primary interlock relay and secondary interlock switch contacts fail to open, the monitor fuse blows simultaneously of the monitor switch contacts.

Before replacing a blown monitor fuse, test the primary interlock relay, door sensing switch, monitor switch and secondary interlock switch for proper operation. (Refer to section “Test Procedures”.)

with closing

Door Open Mechanism

The door is opened by pushing the open button on the control panel. When the open button is pushed, the open button pushes up the switch lever, and then the switch lever

pushes up the latch heads. The latch heads are moved upward and released from the latch hook. Now the door will open.

Door Sensing / Secondary Interlock

Switches

The secondary interlock switch is mounted in the lower

position of the latch hook and the door sensing switch in the primary interlock system is mounted in the upper

position of the latch hook. They are activated by the

latch heads on the door. When the door is opened, the switches interrupt the circuit to all components, except the oven lamp. A cook cycle cannot take place until the

door is firmly closed thereby activating both interlock

switches. The primary interlock system consists of the

door sensing switch and the primary interlock relay lo-

cated on the control panel circuit board.

/ Switch

NOTE: MONITOR FUSE AND MONITOR SWITCH

ARE REPLACED AS AN ASSEMBLY.

Monitor

SERVICING

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.

Before replacing a blown monitor fuse, test the door sensing switch, primary interlock relay, secondary interlock switch and monitor switch for proper operation. tion.)

Whenever troubleshooting is performed, the power supply must be disconnected. In some cases it may be necessary to connect the power supply after the outer case cabinet has been removed. In this event,

1. Disconnect the power supply cord, and then remove outer case cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. Disconnect the leads to the primary of the power transformer.

5. Ensure that the leads remain isolated from other components and oven chassis by using insulated tape.

6. After the above procedure install the outer case cabinet and reconnect the power supply cord.

When the testing is completed

1. Disconnect the power supply cord, and then remove outer case

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. Reconnect the leads to the primary of the power transformer.

5. Re-install the outer case (cabinet).

6. Reconnect the power supply cord after the outer case is installed.

7. Run the oven and check all functions.

(Refer to “Test Procedure” sec-

Troubleshooting Guide

Off Condition

Problem Possible Cause Test Procedure

Home fuse blows when power cord is Shorted power cord or wire harness

plugged into the wall receptacle.

Monitor fuse blows when power is ap- Shorted power cord or wire harness

plied.

Display does not illuminate when Shorted or open wiring

power cord is plugged in.

Display does not operate properly Primary interlock relay or door sens- Procedure E when STOP/CLEAR button is ing switch touched.

Oven lamp does not light with door Shorted or open wiring opened.

Secondary interlock or monitor Procedure E switch

Monitor switch or monitor fuse Oven temperature fuse Control unit Procedure G

Control unit Key unit unit

Monitor fuse

1 Oven temperature fuse 1 Procedure F

Oven lamp or socket Control unit Relay (RYI)

Check or replace

Check or replace Procedure E Procedure F

Procedure G Procedure K Check or replace Procedure E

Check or replace Procedure G Procedure H

Problem

mamp does not light at all.

Oven lamp lights, but fan motor and turntable motor do not operate.

Oven does not go into cook cycle when START button is touched.

Oven seems to be operating but

little or no heat is produced in oven load. (incompletely cooked or not cooked at all at the end of cook cycle.)

Oven goes into a cook cycle but extremely uneven heating is produced in oven load (food).

-does not cook properly when programmed for Cooking Power P-50 (MED.) mode. (Operates properly on Cooking Power P-HI (HIGH) mode.)

Oven goes into COMPU DEFROST but food is not defrosted well

Troubleshooting Guide

Cook Condition Possible Cause

Shorted or open wiring Oven lamp or socket Control unit Shorted or open wiring Cooling fan motor Turntable motor Shorted or open wiring

Primary interlock system Monitor fuse Magnetron or oven temperature

fuse

Relay (RYl) Shorted or open wiring Magnetron

Power transformer Rectifier assembly H .V. capacitor Primary interlock system Shorted or open wiring

Turntable motor

Low voltage Dirty oven cavity Wrong operation Shorted or open wiring

Control unit

Magnetron Procedure A Wrong operation

Low voltage Dirty oven check Check Compu Defrost

Check or replace Check or replace

Procedure G Check or replace Check or replace Check or replace

Check or replace

Procedure E

Procedure F

Procedure H

Check or replace

Procedure A Procedure B Procedure C Procedure D Procedure E Check or replace Check or replace Check

Check Check Check or replace

Procedure G

Check Check

Procedure J

Test Procedure

TEST PROCEDURES

Procedure Letter

A .

. Power Transformer

Magnetron Assembly Test

1. Disconnect the power supply cord, and then remove outercase cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

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 IQ.

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 (shorted) and must be replaced.

6. Reconnect all leads removed from components during testing.

7. Re-install the outercase cabinet.

8. Reconnect the power supply cord after installing the outer case cabinet.

9. Run the oven and check all functions.

MICROWAVE OUTPUT POWER The following test procedure should be carried out with the microwave oven in a fully assembeled

condition (outer case fitted). HIGH VOLTAGES ARE PRESENT DURING THE COOK CYCLE, SO EXTREME CAUTION

SHOULD BE OBSERVED

Power output of the magnetron can be measured by performing a water temperature rise test. This test should only be used if above tests do not indicate a faulty magnetron and there is no defect in the following components or wiring: high voltage rectifier, high voltage capacitor and power transformer. This test will require a 16 oz. (453~~) measuring cup and an accurate mercury thermometer or thermocouple type temperature tester. For accurate results, the following procedure must be fol-

lowed:

Fill the measuring cup with 16 oz. (453~~) of tap water and measure the temperature of the water with a thermometer or thermocouple temperature tester. through the water until the temperature stabilizes. Place the cup of water in the oven. Operate oven on HIGH selecting 62 seconds cook time. Allow the water to heat. Remove the cup from the oven and again measure the temperature, making sure to stir the thermometer or thermocouple through the water until the maximum temperature is recorded. Subtract the cold water temperature from the hot water temperature. The normal result should be 38” to 78°F (21 O to 42.6OC) rise in temperature. If the water temperatures are accurately measured and are tested for the required time period the test results will indicate if the magnetron tube has low power output (low rise in water temperature) which would extend cooking time or high power output (high rise in water temperature) which would reduce cook time. Because cooking time can be adjusted to compensate for power output, the magnetron tube assembly should be replaced only if the water temperature rise test indicates a power output well beyond the normal limits. The test is only accurate if the power supply line voltage is 120 volts and the oven cavity is clean.

1. Disconnect the power supply cord, and then remove outer case cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. Disconnect the primary input terminals and measure the resistance of the transformer with an ohmmeter. Check for continuity of the coils with an ohmmeter. On the R X 1 scale, the resistance of the primary coil should be less than 1 Q and the resistance of the high voltage coil should be approximately 900; the resistance of the filament coil should be less than IQ.

5. Reconnect all leads removed from components during testing.

6. Re-install the outercase cabinet.

7. Reconnect the power supply cord after installing the outer case cabinet.

8. Run the oven and check all functions.

Component Test

Stir the thermometer or thermocouple

Record the temperature of the water.

TEST PROCEDURES

Procedure Letter

C .

High Voltage Rectifier Test

1. Disconnect the power supply cord, and then remove outer case cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. 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. If a short is indicated in both directions, or if an infinite resistance is read in both directions,

the rectifier is probably defective and should be replaced.

5. Reconnect all leads removed from components during testing.

6. Re-install the outer case cabinet.

7. Reconnect the power supply cord after installing the outer case cabinet.

8. Run the oven and check all functions.

Component Test

Note: Be sure to use an Ohm-Meter that will supply a forward bias voltage of more than 6.30 Volts.

D . High Voltage Capacitor Test

(Discharge the high voltage capacitor before touching any oven components or wiring.)

1. Disconnect the power supply cord, and then remove outercase.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4 If the capacitor is open, no high voltage will be available to the magnetron. Disconnect input leads

and check for short or open between the terminal using an ohmmeter. Checking with a high ohm scale, if the high voltage capacitor is normal, the meter will indicate continuity initially and once the capacitor is charged an open circuit. If the above is not the case, check the capacitor with an ohmmeter to see if it is shorted between each terminal and case. If it is shorted, replace the capacitor.

5. Reconnect all leads removed from components during testing.

6. Re-install the outercase (cabinet).

7. Reconnect the power supply cord after the outer case is installed.

8. Run the oven and check all functions.

. Secondary Interlock Switch Test

1. Disconnect the power supply cord, and then remove outercase.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4 Isolate the switch and connect the ohmmeter to the common (COM) and normally open (NO) termi-

nal of the switch. The meter should indicate an open circuit with the door open and a closed circuit with the door closed. If improper operation is indicated, replace the secondary interlock switch.

5. Reconnect all leads removed from components during testing.

6. Re-install the outercase (cabinet).

7. Reconnect the power supply cord after the outer case is installed.

8. Run the oven and check all functions.

Primary Interlock System Test

Door Sensing Switch

1. Disconnect the power supply cord, and then remove outercase.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. Isolate the switch and connect the ohmmeter to the common (COM) and normally open (NO) termi-

nal of the switch. The meter should indicate an open circuit with the door open and a closed circuit

with the door closed. If improper operation is indicated, replace the door sensing switch.

5. Reconnect all leads removed from components during testing.

6. Re-install the outercase (cabinet).

7. Reconnect the power supply cord after the outer case is installed.

8. Run the oven and check all functions.

TEST PROCEDURES

Procedure Letter

. Continued

Primary Interlock Relay (RY-2)

1. Disconnect the power supply cord, and then remove outer case cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. Disconnect two (2) wire leads from the relay on the printed circuit board in the control panel assembly. The relay is located on the bottom portion of the circuit board on the backside of the control panel assembly. Connect an ohmmeter to the male terminals and observe the meter reading. The relay contacts should be open. or the circuit board.

5. Reconnect all leads removed from components during testing.

6. Re-install the outer case cabinet.

7. Reconnect the power supply cord after installing the outer case cabinet.

8. Run the oven and check all functions.

Monitor Switch Test

1. Disconnect the power supply cord, and then remove outer case cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4 Disconnect the oven from the power supply.

Before performing this test, make sure that the secondary interlock switch and primary interlock relay are operating properly referring to the above Switch Test Procedure. Disconnect the wire lead from the monitor switch (NC) terminal.

Check the monitor switch operation by using the ohmmeter as follows: When the door is open, the meter should indicate a closed circuit. With the door open, take a screw driver and push in the monitor switch actuator located through the lower latch hole on the faceplate of the cavity. The meter should indicate a open circuit.

If improper operation is indicated, the monitor switch may be defective and should be replaced.

After testing the monitor switch, reconnect the wire lead to the monitor switch (NC) terminal and

check continuity of the monitor circuit.

5. Reconnect all leads removed from components during testing.

6. Re-install the outer case cabinet.

7. Reconnect the power supply cord after installing the outer case cabinet.

8. Run the oven and check all functions.

Component Test

If the relay contacts are closed, replace the primary interlock relay

Red Wire Connected to Normally Closed Terminal

Notel: Connect ohmmeter

Note2: Use screwdriver to engage

monitor switch actuator.

Common Terminal

TEST PROCEDURES

IEE?

Procedure Letter

Continued

Open Monitor Fuse

I. Disconnect the power supply cord, and then remove outer case cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor. 4 If the monitor fuse is open, perform the tests for the primary interlock system, secondary interlock

switch and the monitor switch according to the procedure outlined in this section. Adjust or replace

the secondary interlock and door sensing switches.

5. Reconnect all leads removed from components during testing.

6. Re-install the outer case cabinet.

7. Reconnect the power supply cord after installing the outer case cabinet.

8. Run the oven and check all functions.

F . Temperature Fuses

I. Disconnect the power supply cord, and then remove outer case cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. A continuity check across either of the temperature fuse terminals should indicate a closed circuit unless the temperature of the magnetron temperature fuse reaches 150°C or the oven cavity fuse reaches 150°C. An open magnetron temperature fuse indicates overheating of the magnetron assembly while an open oven fuse indicates overheating of the oven cavity. If a temperature fuse indicates an open circuit, exchange that temperature fuse and check for a restricted air duct, restricted air flow to the magnetron and oven cavity through the vent holes of the oven cavity, espe-

cially the air duct and cooling fan assembly.

5. Reconnect all leads removed from components during testing.

6. Re-install the outercase cabinet,

7. Reconnect the power supply cord after installing the outer case cabinet.

8. Run the oven and check all functions.

Component Test

. Touch Control Panel Assembly Test

The touch control panel consists of circuits including semiconductors such as LSI, ICs, etc. Therefore, unlike conventional microwave ovens, proper maintenance can not be performed with only a voltmeter and ohmmeter. In this service manual, the touch control panel assembly is divided into two

control units, Control Unit and Key Unit. Troubleshooting by unit replacement is described according

to the symptoms indicated.

Before testing

1. Disconnect the power supply cord, and then remove outer case cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. Disconnect the leads to the primary of the power transformer.

5. Ensure that these leads remain isolated from other components and oven chassis by using insu-

lated tape.

6. After that procedure, re-connect the power supply cord.

Procedure Letter

G . Continued

Touch Control Panel Assembly Test

1. Key Unit

1. Disconnect the power supply cord, and then remove outer case cabinet

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. Check unit ribbon connection before replacement.

5. Reconnect all leads removed from components during testing.

6. Re-install the outercase (cabinet).

7. Reconnect the power supply cord after the outer case is installed.

8. Run the oven and check all functions. The following symptoms indicate a defective key unit. Replace the key unit. a) When touching the pads, a certain pad produces no signal at all. b) When touching a number pad, two figures or more are displayed. c) When touching the pads, sometimes a pad produces no signal.

If the key unit is defective.

1. Disconnect the power supply cord, and then remove outercase cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. Replace the key unit.

5. Reconnect all leads removed from components during testing.

6. Re-install the outercase cabinet.

7. Reconnect the power supply cord after the outer case is installed.

8. Run the oven and check all functions.

2. Control Unit The following symptoms indicate a defective control unit. Before replacing the control unit, perform the Key unit test (Procedure K) to determine if control unit is faulty.

2-l 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. d) The corresponding segments of all digits do not light up; or they continue to light up. e) Wrong figure appears. f) A certain group of indicators do not light up. g) All the segments of a digit flicker.

2-3 Other possible problems caused by defective control unit.

a) Buzzer does not sound or continues to sound. b) Clock does not operate properly. c) Cooking is not possible.

When testing is completed,

1. Disconnect the power supply cord, and then remove outer case cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. Reconnect all leads removed from components during testing.

5. Re-install the outercase cabinet.

6. Reconnect the power supply cord after installing the outer case cabinet.

7. Run the oven and check all functions.

Component Test

TEST PROCEDURES

Procedure Letter

H . Relay Test

1. Disconnect the power supply cord, and then remove outer case cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. Disconnect the leads to the primary of the power transformer.

5. Ensure that the leads remain isolated from other components and oven chassis by using insulated tape.

6. After the above procedure , reconnect the power supply cord.

7. Check voltage between Pin No. 1 of the 2 pin connector (A) and the common terminal of the relay

RY2 on the control unit with A.C. voltmeter. The meter should indicate 120 volts. If not, check oven

circuit.

RY-1 and RY-2 Relay Test

These relays are operated by D.C. voltage.

Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking operation.

DC. voltage indicated . . . . . . . . . , . . . . . . . . . . . . Defective relay.

DC. voltage not indicated . . . . . . . . . . . . . . . . . . . Check diode which is connected to the relay

1 Relay Symbol 1 Operational Voltage

RY 1 1 Approx. 11.8 V DC

IRY2

Component Test

coil. If diode is good, control unit is defective.

1 Connected Components / Oven lamp/Turntable motor/Cool&g fan motor

1 Approx. 10.7 V DC ( Power transformer

8. Disconnect the power supply cord.

9. Open the door and block it open.

10. Discharge the high voltage capacitor.

11. Reconnect all leads removed from components during testing.

12. Re-install the outer case cabinet.

13. Reconnect the power supply cord after installing the outer case cabinet.

14.Run the oven and check all functions

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, which acts as a fuse.

1 Foil Pattern check and repairs

1. Disconnect the power supply cord, and then remove outer case cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. Follow the troubleshooting guide given below for repair:

rSteps 1 Occurrence Cause or Correction

1 Only pattern at “a” is broken.

2 I Pattern at “a” and “b” are broken

I * Insert jumper wire Jl and solder. I* Insert the coil RFILNOO~~WREO between “c” and “d”. 1

TEST PROCEDURES

Procedure Letter

I .

Continued

Procedures to be taken when the foil pattern of the printed wiring board (PWB) is open

5. Make a visual inspection of the varistor burn

6. Reconnect all leads removed from components during testing.

7. Re-install the outercase (cabinet).

8. Reconnect the power supply cord after installing the outer case cabinet.

9. Run the oven and check all functions.

2. Follow the troubleshooting guide given below. repairs are finished.

Component Test

damage and test the transformer with an ohmmeter for the presence of a layer short-circuit (check the primary coil resistance which is approximately 540 I(z & 20%). If any abnormal condition is detected, replace the defective

part(s) =

If indicator does not light up after above check and

1. Disconnect the power supply cord, and then remove outer case cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. Disconnect the leads to the primary of the power transformer.

5. Ensure that the leads remain isolated from other components and oven chassis by using insulated tape.

6. After the above procedure, reconnect the power supply cord.

7. Follow the troubleshooting guide given below for repair.

Steps

8. Disconnect the power supply cord, and then remove the outer case.

9. Open the door and block it open.

10. Discharge the high voltage capacitor.

11. Reconnect all leads removed from components during testing.

12. Re-install the outer case cabinet.

13. Reconnect the power supply cord after the outer case cabinet is installed.

14. Run the oven and check all functions.

Occurrence

The rated AC voltage is not present between Pin No.1 of the 2-pin connector (A) and the common terminal of the relay RYI .

The rated AC voltage is present at primary side of low Voltage transformer.

Cause or Correction

Check supply voltage and oven power cord

Low voltage transformer or secondary circuit defective. Check and repair.

Procedure Letter

Component Test

K .

Compu Defrost Test

WARNING : The Oven should be fully assembled before following procedure.

1. Place one cup of water in the center of the turntable tray in the oven cavity.

2. Close the door, touch the “COMPU DEFROST” pad twice.

3. Touch the number pad “5” and Then touch the “START” pad.

4. The oven is in “COMPU DEFROST” cooking mode.

5. The oven will operate as follows:

Weight 1st Stage

Level

0.5 lb 60%

6. If improper operation is indicated, the control unit is probably defective and should be checked.

Time

27sec.

2nd Stage

Level Time

40% 17 sec.

Key Unit Test

1. Disconnect the power supply cord, and then remove outer case cabinet.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. If the display fails to clear when the STOP/CLEAR pad is depressed, first verify the flat ribbon is making good contact and verify that the door sensing switch operates properly (contacts are closed when the door is closed and open when the door is open). disconnect the flat ribbon cable that connects the key unit to the control unit and make sure the door sensing switch is closed (either close the door or short the door sensing switch connector).

Use the key unit matrix indicated on the control panel schematic and place a jumper wire between

the pins that correspond to the STOP/CLEAR pad making momentary contact. If the control unit

responds by clearing with a beep the key unit is faulty and must be replaced. not respond, it is faulty and must be replaced.If a specific pad does not respond, the above method may be used (after clearing the control unit) to determine if the control unit or pad is at fault.,

5. Reconnect all leads removed from components during testing.

6. Re-install the outer case cabinet.

7. Reconnect the power supply cord after installing the outer case cabinet

8. Run the oven and check all functions.

If the door sensing switch is good,

If the control unit does

G-8

- G-9 - 5

- G-10 -

- G-11 -

_ ~-12 _ Beverage CE

Frozen entrees

G-7 G-6 - G-5

Power

Level

Casserol

Popcorn

G-4 G-3

2 1

7 6

START

MINUTE

PLUS

Fresh

Vegetables

Timer Clock

G-2 . . G-l -

COMPU

DEFROST Plate

Dinner

OUTLINE OF TOUCH CONTROL PANEL

The touch control section consists of the following units

as shown in the touch control panel circuit: (1) Key Unit (2) Control Unit (The Control Unit consists of Power Unit and LSI unit).

The principal functions of these units and their related

signals are explained below.

Key Unit

The key unit is composed of a matrix. Signals generated in the LSI are sent to the key unit through P20, P21, P22,

P23, P24, P25, P26 and P27. When a key pad is touched, a signal is completed through the key unit and passed back to the LSI through

P41-P45 and AN0 to perform the function that was requested.

Control Unit

The Control unit consists of the following:

1. Synchronizing Signal Circuit

The Power source synchronizing signal is available in order to compose a basic standard time in the clock circuit. It accompanies a very small error because it works on commercial frequency.

2. ACL Circuit

A circuit to generate a signal which resets the LSI to the initial state when power is applied.

Buzzer Circuit

3. The buzzer is responsive to signals from the LSI to emit Audible sounds (key touch sound and completion sound).

Door Sensing Switch

A switch to “tell” the LSI if the door is open or closed.

Relay Circuit

5. A circuit to drive the magnetron, fan motor, turntable

motor and oven lamp.

6. Indicator Circuit This circuit consists of 22 segmenets and 3 com-

mon electrodes using a liquid Crystal Display.

7. Back Light Circuit

A circuit to drive the back light (Light emmitting diodes LDI -LD4).

8. Power Source Circuit

This circuit generates voltage 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.

Symbol Voltage Application vc - 5v

LSI (ICI),

DESCRIPTION OF LSI

LSI

The I/O signals of the LSI (IZA495DR) is detailed in the following table.

Pin No. Signal

I/O Description

1-2 VL2-VLI IN Power source voltage input terminal.

Standard voltage for LCD.

3-6

AN7-AN4 IN

Terminal to change functions according to the Model.

By using the AID converter contained in the LSI, DC voltage in accordance with the Model in

operation is applied to set up its cooking constant. 7 P63 8

AN2

OUT

Terminal not used.

IN Input terminal to judge the Model.

Connected to GND through the pull-down resistor R78 9 AN1 IN

To input signal which communicates the door open/close information to the LSI.

Door close ‘I” level signal (OV) Door open “H” level (5V).

AN0

Input terminal to judge the Model.

One of the signals P20-P27 will be input into AN0 through one of Gl-G8 lines on key matrix.

the LSI will judge the model by this signal.

II-13 P57-P57

14 CNTRO

OUT Terminal not used. OUT

Signal to sound Buzzer (2.0 kHz).

A: key touch sound B: completion sound

turn on and off shut off relay RYI. The square waveform voltage is delivered to the RY-1

driving circuit and RY-2 control circuit.

16 P52

OUT

Magnetron high-voltage circuit driving signal.

To turn on and off cook relay RY2. In high operation, the signals holds “H” level during micro-

wave cooking and ‘I” level while not cooking. In other cooking modes (variable cooking) the

signal turns to “H” level and ‘I_” level in repetition according to the power level.

--------------_-----

P-HI

PTkI 24sec.

(ON and OFF times for other power level)

17-18 P51-50 OUT Terminal not used.

P47-P46

P45

OUT Terminal not used.

Signal coming from touch-key.

19-20

When either G-12 line on key matrix is touched, a corresponding signal out of P20-P27 will be

input into P45. When no key is touched, the signal is held at “H” level.

During Cooking

+I- - - - yii’

H: GND

1 I

1 Pin No. 1 Signal 1 I/O 1 Description

1 22 1 P44 / IN 1 Signal similar to P45.

When either G-l 1 line on key matrix is touched, a corresponding signal will be inputted into P44.

/ 23 ( P43 1 IN / Signal similar to P45.

When either G-l 0 line on key matrix is touched, a corresponding signal will be inputted into P43.

24 INTO IN Signal synchronized with commercial power source frequency.

This is the basic timing for time processing of LSI.

H: +5V

16.7 msec.

/ 25 / P41 / IN / Signal similar to-P45

26 1 P40 1 IN 1 Connected to GND. through the pull down of resistor R90.

1 28-29 I PHI-70 I OUT I Terminal not used.

RESET IN Auto-clear terminal.

I 3o I XIN I IN I

/ 32 / VSS I IN 1 Power source voltage: + 5V

34 P26 OUT Key strobe signal.

37 P23 OUT

41-48 49-50

I-

XOUT OUT Internal clock oscillation frequency setting input.

P27 OUT Key strobe signal.

P25 OUT

P24

P22 OUT Key strobe signal.

P21 OUT Key strobe signal.

P20 OUT

P17-IO I OUT ( Terminal not used.

PO7-PO6 1 OUT I Terminal not used.

OUT

When erther G-9 line on key matrix is touched, a corresponding signal will be inputted into P41.

Signal is input to reset the LSI to the initial state when power is supplied. Temporarily set to “L” level the moment power is supplied, at this time the LSI is reset. Thereafter set at “H” level.

Internal clock oscillation frequency setting input.

Output to control oscillation input of XOUT.

The internal clock frequency is set by applying the ceramic filter oscillatior circuit with respect to XIN terminal.

VSS voltage of power source circuit input.

Signal applied to touch-key section. A pulse signal is inputted to P41, P43, P44 and P45 terminal while one of G8 line keys on key matrix is touched.

Signal applied to touch-key section. A pulse signal is inputted to P41, P43, P44 and P45 terminal while one of G7 line keys on key matrix is touched.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is inputted to P41, P43, P44 and P45 terminal while one of G6 line keys on key matrix is touched.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is inputted to P41, P43, P44 and P45 terminal while one of G5 line keys on key matrix is touched.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is inputted to P41, P43, P44 and P45 terminal while one of G4 line keys on key matrix is touched.

Signal applied to touch-key section. A pulse signal is inputted to P41, P43, P44 and P45 terminal while one of G3 line keys on key matrix is touched.

Signal applied to touch-key section. A pulse signal is inputted to P41, P43, P44 and P45 termi-

nal while one of G2 line keys on key matrix is touched.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is inputted to P41, P43, P44 and P45 termi-

nal while one of Gl line keys on key matrix is touched.

L: GND

Pin No. Signal

51-72

SEG21-SEGO

I/O

Description

OUT Segment data signal.

Connected to LCD.

The relation between signals are as follows:

LSI signal (Pin No.) LCD (Pin No.) LSI signal (Pin No.) LCD (Pin No.)

SEG 21 (51) . . . . . . . . . . . . . . . . . Sl SEG 10 (62) . . . . . . . . . . . . . . . . S12

SEG 20 (52) . . . . . . . . . . . . . . . . . S2

SEG 19 (53) . . . . . . . . . . . . . . . . . S3 SEG 8 (64) . . . . . . . . . . . . . . . . S14

SEG 18 (54) . . . . . . . . . . . . . . . . . S4 SEG 7 (65) . . . . . . . . . . . . . . . . S15

SEG 17 (55) . . . . . . . . . . . . . . . . . S5 SEG 6 (66) . . . . . . . . . . . . . . . . S16

SEG 16 (56) . . . . . . . . . . . . . . . . . S6

SEG 15 (57) . . . . . . . . . . . . . . . . . S7

SEG 14 (58) . . . . . . . . . . . . . . . . . S8 SEG 3 (69) . . . . . . . . . . . . . . . . S19

SEG 13(59) . . . . . . . . . . ..I.... S9 SEG 2 (70) . . . . . . . . . . . . . . . . S20

SEG 12 (60) . . . . . . . . . . . . . . . . SIO

SEG 11 (61) . . . . . . . . . . . . . . . . Sll

SEG 9 (63) . . . . . . . . . . . . . . . . S13

SEG 5 (67) . . . . . . . . . . . . . . . . S17

SEG 4 (68) . . . . . . . . . . . . . . . . S18

SEG 1 (71) . . . . . . . . . . . . . . . . S21

SEG 0 (72) . . . . . . . . . . . . . . . . S22

73174

VCCNREF

Connected to GND. 75 AVSS IN Connected to VC 76 COM3

COM2 OUT Common data signal: COMI.

OUT

Terminal not used

Connected to LCD (Pin No. Cl).

78 COMI

OUT

Common data signal: COM2.

Connected to LCD (Pin No. C2). 79 COMO OUT Common data signal: COM3.

Connected to LCD (Pin No. C3). 80 VL3 IN Power source voltage input terminal

Standard voltage for LCD.

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 in-

fluenced by surrounding high voltage power sources,

static electricity charge in clothes, etc. and sometimes it is not fully protected by the built-in protection circuit. In order to protect CMOS LSI, practice the following guidelines:

2. On some models, the power supply cord between the touch control panel and the oven proper is long enough that they may be separated from each other. For those models, therefore, it is possible to check and repair the controls of the touch control panel while keeping it apart from the oven proper: in this case you must short both ends of the door sensing switch (on PWB) of the touch control panel with a jumper, which brings about an operational state that is equivalent to the oven door being closed. As for the sensor-related controls of the touch control panel, checking them is possible if dummy resistor(s) with resistance equal to that of the controls are used.

1. When storing and transporting LSI, thoroughly wrap them in aluminum foil. Also wrap all PW boards in aluminum foil.

2. When soldering, the technician should use a grounding strap as shown in the figure and use a grounded soldering iron and work table.

. .

Approx. 1 Ma

li?l

Servicing of Touch Control Panel

We describe the procedures to permit servicing of the

touch control panel of the microwave oven and the precautions you must take when doing so. To perform the servicing, power to the touch control panel is available either from the power line of the oven itself or from an external power source.

Servicing The Touch Control Panel With The Oven Power Supply

Servicing The Touch Control Panel With An

External Power Supply

Disconnect the touch control panel completely from the oven proper, and short both ends of the door sensing switch (on PWB) of the touch control panel, which activates an operational state that is equivalent to the oven door being closed. Connect an external power source to the power input terminal of the touch control panel, then it is possible to check and repair the controls of the touch control panel; it is also possible to check the sensor-related controls of the touch control panel by using the dummy resistor (s).

Servicing Tools

Tools required to service the touch control panel assem-

bly.

1. Soldering iron: 30W (It is recommended to use a soldering iron with a grounding terminal.)

2. Oscilloscope: DC-IOMHz type or more advanced model.

3. Hand tools.

Single beam,

frequency range:

Other Precautions

The high voltage transformer of the microwave oven is still live during servicing and presents a hazard.

When checking the performance of the touch control

panel, put the outer cabinet on the oven to avoid touch-

ing the high voltage transformer or unplug the primary terminal (connector) of the high voltage transformer to turn it off; the end of such connector must be insulated

with an insulating tape. After servicing, be sure to re-

connect the leads to their original locations.

1. On some models, the power supply cord between the touch control panel and the oven itself is so short that the two can’t be separated. ‘For those models, check

and repair all the controls (sensor-related ones included) of the touch control panel while keeping it connected to the oven.

Before turning on the power source of the control unit, remove the aluminum foil applied for preventing static electricity.

Connect the connector of the key unit to the control unit being sure that the lead wires are not twisted.

After aluminum foil is removed, be careful that abnormal voltage due to static electricity etc. is not applied to the input or output terminals.

Attach connectors, electrolytic capacitors, etc. to

PWB, making sure that all connections are tight.

Be sure to use specified components where high pre-

cision is required.

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..

oid possible exposure to microwave energy. Please follow the

instructions below before operating the oven.

1. Disconnect the power supply cord.

2. Visually check the door and cavity face plate for damage (dents, cracks, signs of arcing etc.).

Carry out any remedial work that is necessary before

operating the oven.

Do not operate the oven if any of the following condi-

tions exist;

1. Door does not close firmly.

2. Door hinge, support or latch hook is damaged.

3. The door gasket or seal is damaged.

4. The door is bent or warped.

5. There are defective parts in the door interlock system.

6. There are defective parts in the microwave gener-

ating and transmission assembly.

7. There is visible damage to the oven.

Do not operate the oven:

1. Without the RF gasket (Magnetron).

2. If the wave guide or oven cavity are not intact.

3. If the door is not closed.

4. If the outer case cabinet is not fitted.

To prevent electric shock, take the following precautions.

1. Before wiring.

1) Disconnect the power supply cord.

2) Open the door and block it open.

3) Discharge the high voltage capacitor and wait for 60 seconds.

2. Don’t let the wire leads touch the following parts;

1) High voltage parts:

Magnetron, High voltage Transformer, High volt-

age capacitor and High voltage rectifier assembly.

2) Hot parts: Oven lamp, Magnetron, High voltage Transform-

er and oven cavity.

3) Sharp edge: Bottom plate, oven cavity, waveguide, flange, chassis support and other metallic plate.

4) Movable parts (to prevent a fault) Fan blade, Fan motor, Switch , Switch lever, and Open button.

3. Do not catch the wire leads in the outer case cabinet.

4. Insert the positive lock connector until its pin is locked and make sure that the wire leads do not come off even if the wire leads are pulled.

5. To prevent an error function, connect the wire leads correctly, referring to the Wiring Diagram.

Please refer to “OVEN PARTS, CABINET PARTS, CONTROL PANEL PARTS, DOOR PARTS” When carrying out any of the following removal procedures:

Outer Case Removal

left portion of rear cabinet using a T20H Torx type or

GTXH20-100 screw driver.

4. Remove the two screws (2) from the rear of outer case.

2. Discharge the high voltage capacitor before touching any oven components or wiring.

To remove the outer case, proceed as follows.

Disconnect the power supply cord.

Open the oven door and block it open.

2. Remove the two screws (2) from the upper and lower

5. Slide the entire case back about 1 inch (3cm) to free it from retaining clips on the cavity face plate.

6. Lift entire case from the unit.

When replacing the outer case, the 2 special Torx screws must be reinstalled in the same locations.

Power Transformer Removal

Disconnect the power supply cord and remove outer 9. Now the power transformer is free.

case cabinet.

Open the oven door and block it open. Discharge high voltage capacitor.

Disconnect wire leads of the main wire harness and

H.V. wire from power transformer.

Disconnect the lead from magnetron filament.

Disconnect the leads of the power transformer from

6. high voltage capacitor.

Remove the four (4) screws holding the transformer

to base plate.

Remove the transformer.

Re-install

Rest transformer on baseplate with its primary terminals toward oven face plate.

Secure transformer with four (4) screws to baseplate.

Reconnect the wire leads (primary and high voltage) to transformer and filament leads of transformer

to magnetron and high voltage capacitor. Refer to

“Wiring Diagram”.

Re-install outercase cabinet and check that oven is

operating properly.

High Voltage Rectifier and High Voltage

Capacitor Removal

When replacing the high voltage rectifier and high voltage capacitor, the ground side terminal of the high voltage rectifier must be secured firmly with a ground-

ing screw.

Disconnect the power supply cord and remove outer

case cabinet.

Open the oven door and block it open.

Discharge high voltage capacitor.

Remove one (1) screw holding the capacitor band

4. and the high voltage rectifier assembly to the base

Magnetron Removal

Disconnect the power supply cord and remove outer

case cabinet.

Open the oven door and block it open.

Discharge high voltage capacitor.

Disconnect wire leads from the magnetron.

Remove the one (1) screw holding chassis support to magnetron and magnetron duct. Slide the magnetron duct slightly so that two (2) screws at left hand

plate.

Disconnect the wire lead of high voltage rectifier assembly from the magnetron.

Disconnect terminals of rectifier assembly from capacitor and magnetron. High voltage rectifier assembly is now free.

Do not replace only high voltage rectifier. When replacing it, replace the entire high voltage rectifier assembly.

side of the magnetron appear.

6. Carefully remove the four (4) screws holding magnetron to waveguide flange.

7. Remove the magnetron with care so that the magnetron antenna is not hit by any metal objects around the tube.

8. Now, the magnetron is free.

(RDA1504U)

COMPONENT REPLACEMENT / ADJUSTMENT PROCEDURE

Magnetron Installation

Install magnetron assembly to the waveguide flange

1. with care to prevent damage to the magnetron tube.

Secure the magnetron with four (4) screws. Hold the chassis support to the magnetron and mag-

netron duct with one (1) screw.

Connect wire leads to the magnetron . Re-install outer case and check that the oven is oper-

Control Panel Assembly Removal

Disconnect the power supply cord and remove outer case cabinet. Open the oven door and block it open.

Discharge high voltage capacitor.

Disconnect wire leads from panel components.

Remove the one (1) screw holding the control panel. key unit to the correct position of the control panel.

Re-adjust the clip holding panel assembly to oven 3. Stick the key unit firmly to the control panel frame by

flange. rubbing with soft cloth.

Remove control panel assembly by sliding it upward. Note: Handle the LSI unit carefully so that there is no exNow, individual components can be removed. cessive force applied to the ribbon connection.

NOTE:

Oven Lamp and Lamp Socket Removal

1. Disconnect the power supply cord and remove outer 6. Pull the wire leads from the oven lamp socket by

case cabinet. Open the oven door and block it open.

Discharge high voltage capacitor.

Pull the wire leads from the oven lamp socket with

the flat type small screw driver.

Remove the oven lamp socket from the magnetron

duct by turning the socket counterclockwise.

Turntable Motor

Do not drop the turntable motor cover into the oven after cut-

ting the bridges. Because it will damage the wire leads of the

motor and it is difficult to remove it out of the oven.

Disconnect the power supply cord.

Remove turntable and turntable support from oven

cavity.

Lay the oven on its backside. Remove the turntable 7.

ating properly.

When replacing the magnetron, be sure that the R.F. gasket is in place and that the mounting screws are tightened securely.

(RDA1305U)

1. Before attaching a new key unit, remove remaining adhesive on the control panel frame surface completely with alcohol.

2. When attaching the key unit to the control panel frame, adjust the upper edge and right edge of the

pushing the terminal hole of the oven lamp socket with the small flat type screw driver. -,

7. Remove the oven lamp from the oven lamp socket by

turning the oven lamp.

8. Now, the oven lamp and lamp socket are-free.

Note: (orange) wires must be connected to the terminal with

blue mark on the lamp socket.

Removal

motor cover by snipping off the material in four corners.

When the corners have been snipped off, bend the corner areas flat. No sharp edges must be evident

after removal of the turntable motor cover.

Disconnect wire leads from turntable motor. Remove two (2) screws holding turntable motor to

6. oven cavity. Now turntable motor is free.

SCREW Supplied with

CUTTING PLIER

TURNTABLE MOTOR

COVER

8’

replacement motor

Turntable motor cover removal Turntable motor cover re-install

COMPONENT REPLACEMENT / ADJUSTMENT PROCEDURE

Turntable Motor Re-install

Remove any sharp edges on the turntable motor

cover and the base plate with cutting pliers.

Insert the edge of motor cover into tab on the base

plate.

Cooling Fan Motor Removal

Disconnect the power supply cord and remove outer

case cabinet.

Open the oven door and block it open.

Discharge the high voltage capacitor.

Disconnect the wire leads from the fan motor. Remove two (2) screws holding the fan motor to the

5. back plate of the oven cavity. Remove the fan blade from the fan motor shaft ac-

6. cording to the following procedure.

a) Hold the edge of the rotor of the fan motor by using

a pair of groove joint pliers.

3. Secure motor cover with one (1) screw to base plate.

INSTALLATION

Install the fan blade to the fan motor shaft according

to the following procedure

Hold the center of the bracket which supports the

shaft of the fan motor on the flat table. Apply the screw lock tight into the hole (for shaft) of the fan blade.

Install the fan blade to the shaft of the fan motor by

pushing the fan blade with a small, light weight, ball

peen hammer or rubber mallet.

Make sure that no metal pieces enter the gap between the rotor and the stator of the fan motor because the rotor is easily shaven by pliers and metal pieces may be produced. Do not touch the pliers to the coil of the fan motor because the coil may be cut or injured. Do not disfigure the bracket by touching with the pliers.

b) Remove the fan blade from the shaft of the fan mo-

tor by pulling and rotating the fan blade with your

hand.

c) Now, the fan blade will be free.

Do not use this removed fan blade again because the hole (for shaft) may become bigger than a standard

one.

Coil , n

Groove joint pliers

View I

ide

Axis

Bracket

Do not hit the fan blade hard when installing because

the bracket may be disfigured.

Make sure that the fan blade rotates smooth after installation. Make sure that the axis of the shaft is not slanted.

2. Install the fan motor to the back plate of the oven cavity with two (2) screws.

3. Connect the wire leads to the fan motor, referring to the wiring diagram.

0 0

These are the positions which should be pinched with pliers

COMPONENT REPLACEMENT/ADJUSTMENT PROCEDURE

Door Sensing Switch /Secondary Interlock

Switch and Monitor Switch Adjustments

Disconnect the power supply cord and remove outer

case cabinet.

Open the oven door and block it open.

Discharge the high voltage capacitor.

If the door sensing switch, secondary interlock switch and monitor switch do not operate properly due to a misadjustment, the following adjustment should be made.

Loosen the two (2) screws holding the latch hook to the oven cavity front flange.

With the door closed, adjust the latch hook by moving it back and forth, and up and down.

In and out play of the door allowed by the upper and lower position of the latch heads should be less than

0.5mm. The vertical position of the latch hook should be placed where the door sensing switch and the secondary interlock switch have activated with the door closed. Secure the screws with washers firmly. Make sure of the door sensing switch operation. If the door sensing switch has not activated with the door closed, loosen the screw and adjust the latch hook position. Check operation of all switches. If each switch has not activated with the door closed, loosen screw and adjust the latch hook position.

Note: After adjustments, make sure of the following:

1. In and out play of the door remains less than 0.5mm when in the latched position. Check the upper position of the latch hook by pushing and pulling the upper portion of the door.

Then check lower portion of the latch hook, by pushing

and pulling the lower portion of the door toward the

oven face. Both results (play of the door) should be

less than 0.5mm.

The door sensing and secondary interlock switches

interrupt the circuit before the door can be opened. Monitor switch contacts close when door is opened.

Re-install outer case and check for microwave leak-

age around the door with an approved microwave

survey meter. (Refer to “Microwave Measurement Procedure.“)

Door Sensing Switch /Secondary Interlock

Switch and Monitor Switch Removal

Disconnect the power supply cord and remove outer case cabinet.

The door sensing and secondary interlock switches

interrupt the circuit before the door can be opened.

Discharge high voltage capacitor.

Disconnect wire leads from switches, fuse and connectors from control panel.

Remove one (1) screw holding control panel to oven

cavity faceplate.

Slide control panel assembly upward and remove

from cavity faceplate.

Open oven door.

Remove two (2) screws holding the latch hook to oven flange.

Remove latch hook from oven flange by lifting up on

flexible tab and pushing latch hook back.

IO. Locate the flexible retaining tabs on the latch hook.

11. Push tab inward and rotate switch counterclockwise to release switch.

Note: For monitor switch, lift switch over boss while ro-

tating counterclockwise.

12.Switch is now free.

E%%E!

DOOR DISASSEMBLY

Removal

1. Disconnect the power supply cord.

2. Push the open button and open the door slightly.

3. Insert a putty knife (thickness of about 0.5mm) into the gap between the choke cover and corner portion of door panel as shown in the figure below to free engaging parts .

4. Pry the lever and lift up the choke cover by inserting a putty knife in the order as shown in the figure below.

5. Release choke cover from door panel.

6. Now choke cover is free from door panel.

Choke Cover

7. Release two(2) pins of door panel from two (2) holes

of upper and lower door hinges by lifting up.

8. Now, door panel is free from oven cavity.

9. Release door panel from eight (8) tabs of door frame

and remove door frame.

1 O.Now, door panel with sealer film is free.

11. Tear sealer film from door panel.

12. Now, door panel is free.

13Slide latch head upward and remove it from door

frame and latch head.

14.Now latch head and latch spring are free.

15. Remove door screen from door frame.

16. Now, door screen is free.

Re-Install

1. Re-install door screen to door frame.

2. Re-install latch spring to the head. Re-install latch spring to the door frame.

3. Re-install door panel to door frame by fitting eight (8) tabs of door frame to eight (8) holes of door panel.

4. Put sealer film on door panel. Refer to “Sealer Film Installation” and on how to handle the new film.

5. Catch two (2) pins of door panel on two (2) holes of upper and lower door hinge.

6. Re-install choke cover to door panel by snapping on to the door panel.

Note: After any service to the door

(A)Make sure that door sensing switch, secondary

Interlock switch, primary Interlock relay and monitor switch are operating properly. (Refer to section “Test Procedures”.)

(B)An approved microwave survey meter should be

used to assure compliance with proper microwave radiation emission limitation standards.

After adjustment, make sure of the following:

Door latch heads smoothly catch latch hook through latch holes, and also latch head goes through the center of the hole.

Deviation of door alignment from horizontal line of cavity face plate is less than 1 .O mm.

Door is positioned with its face depressed toward cavity face plate.

Install the outer case cabinet and check for microwave leakage around the door with an approved microwave survey meter. (Refer to “Microwave Measurement Procedure”.)

Note: The door on a microwave oven is designed to

act as an electronic seal preventing the leakage of microwave energy from the oven cavity during the cooking cycle. This function does not require that the door be air tight, moisture tight, or light tight. Therefore, the occasional appearance of moisture, light or sensing of gentle warm air movement around the oven door is not abnormal and does not indicate leakage of microwave energy from the cavity.

Sealer Film Installation

1. Put adhesive tape on the backing film of the sealer film as shown below.

2. Tear the backing film by pulling the adhesive tape.

3. Put the pasted side of the sealer film on the door panel.

, Sealer film , Backing film

Fb408CW R-409CK

After adjustment of the door, interlock and monitor switches are completed individually or collectively, a INTERLOCK SWITCH TEST and MICROWAVE LEAKAGE TEST must be performed to assure compliance with DHHS (CDRH) Performance Standards for Microwave Ovens.

Interlock Switch Test

Make sure that the door sensing switch, secondary interlock switch and monitor switch are operating properly by checking with an ohmmeter.

Refer to the “Test Procedure” of the door sensing switch, secondary interlock switch and monitor switch.

Microwave Leakage Test

Requirements

1. Microwave leakage limit (Power density limit). The power density of microwave radiation emitted by

a microwave oven shall not exceed 1 mWcm* at any point 5cm or more from the external surface of the oven, measured prior to acquisition by the purchaser, and thereafter (through the useful life of the oven) 5mWcm* at any point 5cm or more from the external surface of the oven.

2. Safety interlock switches.

Primary interlock relay and door sensing switch will prevent microwave radiation emissions in excess of

the requirement as above mentioned, secondary

interlock switch shall prevent microwave radiation emission in excess of 5 mW/cm* at any point 5cm or more from the external surface of the oven.

Preparation For Testing

Before beginning the proceed as follows:

1. Make

sure that the

mally as specified

actual instrument is operating in its instruction booklet.

Note: Survey instruments that comply with the require-

ment for instrumentation 21 CFRI 030.1 O(c)(3)(i), as prescribed by the performance standard for microwave ovens must be used for testing.

measurement of leakage,

actual

nor-

Place the oven tray in the oven cavity. Place the load of 275 I!Z 15ml(9.8 oz.) of tap water ini-

tially at 20 + 5’C (68’F) in the center of the oven cav-

ity. The water container shall be a low form of 600 ml (20 oz.) beaker with an inside diameter of approximately

8.5 cm (3 % in.) and made of an electrically nonconductive material such as glass or plastic. The placing of this standard load in the oven is important not only to protect the oven, but also to insure that any leakage is measured accurately. Set the cooking control on High.

Close the door and put the oven into a cook cycle for several minutes. If the water begins to boil before the survey is completed, replace it with 275ml of cool water.

Leakage Test

Closed-door leakage test (microwave measurement).

1. Grasp the probe of the survey instrument and hold it perpendicular to the gap between the door and the body of the oven.

2. Move the probe slowly, not faster than lin./sec (2.5cm/sec.) along the gap, watching for the maximum indication of the meter.

Check for leakage at the door screen, sheet metal seams and other accessible positions where the continuity of the metal has been breached (eg., around switches, indicator and vents). While testing for leakage around the door pull the door away from the front of the oven as far as is per-

mitted bv the closed latch assemblv. Measure carefully at the point of the highest leakage

and make sure that the highest leakage is no greater than 4 mW/cm2 to allow for measurement uncertainty, and that the secondary interlock switch does turn the oven OFF before any door movement.

a a

Note: After servicing, record data on service invoice

and microwave leakage report.

H.V.

CAPACITOR

MAGNETRON

POWER

TRANQFnRbl~R

Note 2

Note

RED

RY-2

PRIMARY

RELAY

INTERLOCK

BLU/BRN

I 13

N.O.

I !

MONITOR J SWITCH

COM.

GRN

WHT

Schematic Diagram

BLU/ORG

N.O.

WHT

fi a

- w

l-l m 0 0 co D

FUSE

MONITOR

RY-1

l-l

I t)

Door Closed, Cook Off Condition

FUSE

TEMP.

MAGNETRON

I+=

RED

I 1517

TEMP.

CAVITY

&&I

FUSE

t---I

T m::;:

GRYNVHT

WHT

SECONDARY

INTERLOCK

SWITCH

1. Circuits subject to change without notice.

NOTES:

3. Power supply cord terminal marked “N” must be connected to the neutral (Gray & white) wire.

2. Wire color code applies to primary circuits only, not to low-voltage or secondary circuits.

5. The hot (red) wire must be connected to the (finish lead) terminal of the power transformer.

4. Power supply cord grounding screw must be kept tight at all times.

6. Terminal with blue mark on lamp socket must be connected to the (orange) wire.

CN-A

OVEN LAMP TURNTABLE MOTOR FAN MOTOR

MICRO

1 2 3

4 5 6

CN-C 9PIN LEAD WIRE HARNESS

GND

INT

BUZZER OVEN LAMP r

TURNTABLE

MOTOR FAN MOTOR

MICRO

DOOR

SENSING SWITCH SH-6 \

1 I 2 I

\[Clj

Power Unit Circuit

(BROWNER)

DOOR

1 2 3

-E

4zmo’o 63

A9l/rlLtr 23

+-I

1 2 3

- I

I-

1 2

4 5

DIP

BROWNER

SPl

RY3 RY2 MICRO

Printed Wiring Board of Power Unit

PARTS LIST

Contact your nearest SHARP Parts Distributor to order.

For location of SHARP Parts Distributor, Please call Toll-Free;

1-800-BE-SHARP

Ref No. Part No. Q Description

Electrical

l- 1 RC-QZBO18MREO M H.V. Capacitor l- 2 FH-DZB008MRYO M H.V. Diode assembly l- 3 QSOCLBOOGMREO M Oven lamp socket l- 4 RLMPTAO68WREO M Oven lamp l- 5 RMOTEA346WREO M Fan motor l- 6 l- 7 FFS-BAOlG/KIT

l- 8 l- 9 l-10 QFS-TAO13WREO l-11 1-12 RMOTDA211/KIT 1-13 RTRN-BO61MREO M Power transformer 1-14 FACCDB003MREO M Power cord 1-15 QW-QZBO16MREO 1-16 FW-VZB168MREO 1-17

QFSHDBO03MREO M Fuse block

M Monitor switch (V-16G-2C25) & Fuse assembly 1 AF

(2OA-250VAC) QSW-MAllOWREO QFS-TAO14WREO M Cavity Temperature fuse (15O'C) 1

RV-MZA255WREO M Magnetron

FW-VZB125MREO M Stop switch harness

M Sec.

M Magnetron Temperature fuse (15O'C) 1 AE

M T.T. Motor

M H.V. wire A (Transformer - Capacitor) M Main wire harness

interlock & Door sensing switch (V-16G-3C25)

Oven

2- 1 LBNDKBOO7MRPO M H.V. Capacitor band 2- 2 LANGTBO44MRPO M Chassis support 2- 3 PHOK-B018MRFO M Latch hook

2- 4 GDAI-B053MRPO 2- 5 GLEGPB004MRFO M Foot 2- 6 MLEVPBO16MRFO 2- 7 PDUC-B089MRPO 2- 8 NFANPBOO1MREO 2- 9 PDUC-B088MRFO M Fan duct

2-10 --------_---------~ - Oven cavity (Not a replaceable part)

2-11 PCOVPBO73MRPO M Waveguide cover 2-12 GCABUBO64MRPO 2-12 GCABUBO88MRPO M Outer case cabinet (R-408CW) 2-13 FROLPB025MRKO M T.T. Roller assembly

2-14 NTNT-AO95WREO 2-15 PPACGB014MRFO M T.T. Motor packing

2-16 PCUSGB033MRPO

M Base plate

M Latch lever M Magnetron duct M Fan blade

M Outer case cabinet (R-409CK) 1 AV

M T.T. Tray

M Base plate cushion

Qty Code

1 1 AE 1 AE 1 AR 1 AD

2 AE

1 BE 1 AL

BD 1 1 AC 1

AU 1 AF

AB 1

AE 1

AF 1 AR 4

AB 1 AD

1 AF 1 AC

1 1

1 AV 1 AK 1 1

3-l 3-1A QCNCMA275DREO

3-1B

3-1c Cl Dl

CPWBFBO3OMRUO

QCNCMA275DREO FW-VZB169MREO RC-EZA333DREO

RSRCDAO13DREO

Control Panel

M Control unit J 2-pin connector (CN-A)

J 2-pin connector (CN-B) M g-pin wire harness (CN-C) J Capacitor 220pF 25v

J IDiode Bridge (SlNBlO)

1 BL

1 AB 1 AB 1 1

Ref No.

Part No. Q Description

Control Panel

RYl-2 RRLY-A114DREO SPl

Tl RTRNPBO13MREO Tl VRSl

VRSl

3-2 3-3 3-3 3-4 3-4 3-5 3-5

3-6 3-7

3-8

RALM-AO14DREO

RTRNPAllODREO RH-VZBOOlMREO

RH-VZAO32DREO LHLD-BOO7MRFO

FPNLCB23OMRKO FPNLCB231MRKO FUNTKB182MREO FUNTKB183MREO JBTN-BO87MRFO JBTN-B086MRFO

MSPRTAO5OWREO

PSHEPBO23MREO XEPSD30PlOXSO

J Relay J Buzzer (PKM22EPT)

M Transformer

Transformer(Interchangeable)

J M Varistor (470ND-10D)

Varistor(104G471K)(Interchangeable)

J M LED holder

M Control panel assembly (R-408CW) M Control panel assembly (R-409CK) M Key unit (R-408CW) M Key unit (R-409CK) M Open Button (R-408CW) M Open Button

M Button Spring M LED sheet M Screw; Control unit mtg.

(DUl2Dl-lPR(M)) 2

(R-409CK)

Door

4- 1 FCOV-B136MRKO M Door screen assembly(R-409CK) 4- 1 FCOV-B137MRKO M Door screen assembly (R-408CW)

4- 2 FDORFB062MRTO

4- 3 PSHEPB021MREO 4- 4 GCOVHBO38MRFO M Choke cover

4- 5 LSTPPB02lMRFO M Latch head

4- 6 MSPRTAO46WREO 4- 7 HPNL-BO8'7MREO M Door Screen (R-409CK) 4- 7 HPNL-BO88MREO

M Door panel M Sealer film

M Latch spring

M Door Screen (R-408CW)

Qty Code

1 1 1 1

1 1

1 1 1 1 1 1

AP AB AE AD

AQ AW

AE' AE

1 1

AP 1 AW 1 AE 1

AG 1

AE 1 AB

AK 1

Miscellaneous

5- 1 TCAUABO37MRRO 5- 2 TCAUABO38MRRO M DHHS caution label 5- 3 TINSEB204MRRO

M Monitor caution label

M Operation manual

Fasteners

6- 1 6- 2 6- 3 6- 4 6- 5

6- 6 6- 7 6- 8 6- 9

6-10

LX-BZAO41WREO LX-CZ0052WREO XHTSD4OP12RVO LX-BZ0081YBEO XOTSD40P12000

XCPSD30P08000 XCBSD3OPO8000

LX-CZAO38WREO

XHTSD4OPO8RVO

LX-CZAO7OWREO

Screw; Screw; Screw; Screw; Screw;

Base plate. Screw;

Screw; Screw; Screw; Fan motor mtg.

Screw; UL O.C. Cabinet

H.V wire assy. mtg. Latch hook mtg. Power cord mtg. Magnetron mtg.

Power transformer mtg., Chassis support &

T.T. Motor mtg. Temperature fuse mtg. O.C. Cabinet grnd.

1 1 1 AD

1 2 1 4

R-408CW

R-409CK

w -

5 6

1 2 3 4 5 6

Control Panel Assembly

4 A

3 B

Door Assembly

Wire Harnesses

Packing and Accessories

* Actual harnesses may be different than illustrations.

* Non-replaceable items.

TURNTABLE SUPPORT

* PACKING CASE

3 4

SHARF?

‘990 SHARP CORP. (3M3.2E) Printed in U.S.A.

SHARP R408CW, R-409CK Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

TABLE OF CONTENTS

Foreword

WARNING TO SERVICE PERSONNEL

Before Servicing

When the testing is completed

After repairing

SPECIFICATIONS

Grounding Instructions

Key Unit Layout

Description of Operating Sequence

Off Condition

Cooking Condition

OPERATION

DESCRIPTION AND FUNCTION OF COMPONENTS

Cooling Fan Motor

Oven Temperature Fuse

Magnetron Temperature Fuse

Monitor Switch

Monitor Switch Functions

Door Open Mechanism

SERVICING

Troubleshooting Guide

Off Condition

TEST PROCEDURES

D . High Voltage Capacitor Test

Primary Interlock System Test

Monitor Switch Test

Open Monitor Fuse

F . Temperature Fuses

Before testing

H . Relay Test

Procedures to be taken when the foil pattern of the printed wiring board (PWB) is open

OUTLINE OF TOUCH CONTROL PANEL

Key Unit

Control Unit

DESCRIPTION OF LSI

Servicing of Touch Control Panel

Servicing The Touch Control Panel With The Oven Power Supply

Servicing Tools

Other Precautions

Outer Case Removal

Power Transformer Removal

Magnetron Removal

Magnetron Installation

Control Panel Assembly Removal

Oven Lamp and Lamp Socket Removal

Turntable Motor Re-install

Cooling Fan Motor Removal

DOOR DISASSEMBLY

Removal

Re-Install

Sealer Film Installation

Interlock Switch Test

Microwave Leakage Test

Power Unit Circuit

Printed Wiring Board of Power Unit

PARTS LIST

Electrical

Oven

Control Panel

Door

Miscellaneous

Fasteners

Control Panel Assembly

Door Assembly

Wire Harnesses

Packing and Accessories