Sharp R-3A88 User Manual

SERVICE MANU AL

S3614R3A88PX/

MICROWAVE OVEN

R-3A88

MODEL

R-3A88

In interests of user-safety the oven should be restored to its original
condition and only parts identical to those specified should be used.

TABLE OF CONTENTS

Page

CAUTION, MICROWAVE RADIATION................................................................................................................. 1

WARNING..............................................................................................................................................................1

PRODUCT SPECIFICATIONS ............................................................................................................................. 2

GENERAL INFORMATION....................................................................................................................................2

APPEARANCE VIEW ........................................................................................................................................... 3

OPERATION SEQUENCE.................................................................................................................................... 4

FUNCTION OF IMPORTANT COMPONENTS ..................................................................................................... 5

SERVICING .......................................................................................................................................................... 6

TEST PROCEDURE ............................................................................................................................................. 8

TOUCH CONTROL PANEL .................................................................................................................................14

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE ............................................................... 18

MICROWAVE MEASUREMENT ........................................................................................................................ 24

WIRING DIAGRAM ............................................................................................................................................. 25

PICTORIAL DIAGRAM ....................................................................................................................................... 26

CONTROL PANEL CIRCUIT ...............................................................................................................................27

PRINTED WIRING BOARD .................................................................................................................................28

PARTS LIST ....................................................................................................................................................... 29

SHARP CORPORATION

R-3A88

SERVICE MANUAL

R-3A88

MICROWAVE OVEN

R-3A88

GENERAL IMPORTANT INFORMATION

This Manual has been prepared to provide Sharp Corp. Service
engineers with Operation and Service Information.

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

CAUTION

MICROWAVE RADIATION

DO NOT BECOME EXPOSED TO RADIATION FROM
THE MICROWAVE GENERATOR OR OTHER PARTS
CONDUCTING MICROWAVE ENERGY.

Service engineers should not be exposed to the microwave
energy which may radiate from the magnetron or other
microwave generating devices if it is improperly used or
connected. All input and output microwave connections,
waveguides, flanges and gaskets must be secured. Never
operate the device without a microwave energy absorbing
load attached. Never look into an open waveguide or
antenna while the device is energized.

PRODUCT SPECIFICATIONS

APPEARANCE VIEW

OPERATING SEQUENCE

FUNCTION OF IMPORTANT
COMPONENTS

SERVICING AND
TROUBLESHOOTING CHART

TEST PROCEDURE

TOUCH CONTROL PANEL
ASSEMBLY

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 is not any other visible damage with the oven.

Servicing and repair work must be carried out only by trained
service engineers.

All the parts marked "*" on parts list are used at voltages more
than 250V.

Removal of the outer wrap gives access to potentials above
250V.

All the parts marked "∆" on parts list may cause undue
microwave exposure, by themselves, or when they are dam­aged, loosened or removed.

SHARP CORPORATION

OSAKA, JAPAN

COMPONENT REPLACEMENT
AND ADJUSTMENT PROCEDURE

MICROWAVE MEASUREMENT

WIRING DIAGRAM

PARTS LIST

1

R-3A88

PRODUCT SPECIFICATIONS

ITEM DESCRIPTION

Power Requirements 220 Volts

50 Hertz

Single phase, 3 wire earthed
Power Consumption 1.35 kW
Power Output 850 watts nominal of RF microwave energy (IEC 705)

Operating fequency 2450 MHz
Case Dimensions Width 520 mm

Height 305 mm

Depth 389mm
Cooking Cavity Dimensions Width 348 mm

Height 197 mm

Depth 368 mm
Turntable diameter 325mm
Control Complement Touch Control System

Clock ( 1:00 - 12:59)

Timer (0 - 99 minutes 99 seconds)

Microwave Power for Variable Cooking

Repetition Rate;

HIGH ...............................................Full power throughout the cooking time

MEDIUM HIGH ..................................................approx. 70% of Full Power

MEDIUM .............................................................approx. 50% of Full Power

MEDIUM LOW ....................................................approx. 30% of Full Power

LOW....................................................................approx. 10% of Full Power

HELP pad, REHEAT pad

RICE COOK pad

STEAM MENU pad

MORE, LESS pads

INTERNATIONAL MENU pads

SLOW COOK pad

EASY DEFROST pad

NUMBER pads,

POWER LEVEL pad

AUTO START/ pad

STOP/CLEAR pad

INSTANT COOK/START pad
Set Weight Approx. 15 kg

GENERAL INFORMATION

WARNING

THIS APPLIANCE MUST BE EARTHED

IMPOTANT

THE WIRES IN THIS MAINS LEAD ARE COLOURED IN ACCORDANCE WITH THE FOLLOWING CODE:

GREEN-AND-YELLOW : EARTH
BLUE : NEUTRAL
BROWN : LIVE

2

APPEARANCE VIEW

INTERACTIVE

DISPLAY

HELP

REHEAT

RICE COOK

STEAM MENU

INTERNATIONAL MENU

1 Dishes

3 Bread

2

Beverage

1 Rice

3 Porridge

2 Congee

1 Fish

3

Dumpling

2 Meat

Mini pizza

SLOW COOK

POWER LEVEL

INSTANT COOK / START

AUTO START/

STOP / CLEAR

EASY DEFROST

Sukiyaki

Tom Yum Kung

1234

5

6789



O





a

d

g

i

c

b

e

j

l

k
m

f

h

1. Ventilation openings

2. Oven lamp

3. Door hinges

4. Door safety latches

5. See through door

6. Door seals and sealing
surfaces

7. Coupling

8. Door open button

9. Touch control panel

10.Digital readout

11.Wave guide cover

12.Power supply cord

13.Rating label

14.Earth wire

a HELP PAD

Touch to select child lock, language or demonstration modes.
Touch to get cooking information.

3

4

6

7

5

TOUCH CONTROL PANEL

2

11 4

10

14

9

8

12

COOK KG DEF HELP

13

R-3A88

1

Indicator

b REHEAT PAD

Touch to reheat 3 popular menus.

c RICE COOK PAD

Touch to cook rice, congee or porridge.

d STEAM MENU PAD

Touch to cook steam menus.

e. INTERNATIONAL MENUE OADS

Touch to cook 3 international menus.

f SLOW COOK PAD

Touch to cook slowly and longer time.

g EASY DEFROST PAD

Touch to defrost meat by entering weight.

h MORE (

Touch to adjust the doneness of food in one minute increments
during cooking or to increase/decrease the time whilst
programming the REHEAT, RICE COOK, STEAM MENU,
INTERNATIONAL MENU or EASY DEFROST modes.

i NUMBER PADS

Touch to enter cooking times, clock time, weight or quantity of
food.

j AUTO START/CLOCK PAD

Touch to set clock or Auto Start time.

), LESS ( ) PADS

k POWER LEVEL PAD

Touch to select microwave power setting.
If not touched, HIGH is automatically selected.

l STOP/CLEAR PAD

Touch to clear during programming.
Touch once to stop operation of oven during cooking; touch
twice to cancel cooking programme.

m INSTANT COOK/START PAD

Touch once to cook for 1 minute at HIGH or increase by 1 minute
multiples each time this pad is touched during cooking.
Touch to start oven after setting programmes.

3

R-3A88

OPERATION SEQUENCE

OFF CONDITION

Closing the door activates all door interlock switches (1st.
latch switch and 2nd. interlock relay control switch).

IMPORTANT
When the oven door is closed, the monitor switch contacts
(COM-NC) must be open.
When the microwave oven is plugged in a wall outlet, rated
voltage is supplied to the point A3+A5 in the control unit.

Figure O-1 on page 25

1. The display shows SHARP , MICRO- , WAVE
and OVEN .

2. To set any programmes or set the clock, you must first
touch the STOP/CLEAR pad.

3. : appears in the display.

NOTE: When the oven door is opened, the oven lamp

comes on at this time.

MICROWAVE COOKING CONDITION

HIGH COOKING

Enter a desired cooking time with the touching NUMBER
pad and start the oven with touching START pad.

Function sequence

Figure O-2 on page 25

CONNECTED COMPONENTS RELAY
Oven lamp, Fan motor, Turntable motor RY1
Power transformer RY2

1. Rated voltage. is supplied to the primary winding of the
power transformer. The voltage is converted to about 3.3
volts A.C. output on the filament winding and high
voltage of approximately 2000 volts A.C. on the secondary
winding.

2. The filament winding voltage (3.3 volts) heats the
magnetron filament and the high voltage (2000 volts) is
sent to the voltage doubling circuit, where it is doubled to
negative voltage of approximately 4000 volts D.C..

3. The 2450 MHz microwave energy produced in the
magnetron generates a wave length of 12.24 cm. This
energy is channelled through the waveguide (transport
channel) into the oven cavity, where the food is placed to
be cooked.

4. When the cooking time is up, a signal tone is heard and
the relays RY1+RY2 go back to their home position. The
circuits to the oven lamp, power transformer, fan motor
and turntable motor are cut off.

5. When the door is opened during a cook cycle, the
switches come to the following condition

CONDITION
DURING DOOR OPEN

SWITCH CONTACT COOKING (NO COOKING)
1st. latch switch COM-NO Closed Open

2nd. interlock relay
control switch COM-NO Closed Open

Monitor switch COM-NC Open Closed

The circuits to the power transformer, fan motor and
turntable motor are cut off when the 1st. latch switch and
2nd. interlock relay control switch are made open. The
oven lamp remains on even if the oven door is opened
after the cooking cycle has been interrupted, because
the relay RY1 stays closed. Shown in the display is the
remaining time.

6. MONITOR SWITCH CIRCUIT
The monitor switch is mechanically controlled by oven
door, and monitors the operation of the 1st latch switch
and 2nd. interlock relay.

6-1 When the oven door is opened during or after the cycle

of a cooking program, the 1st. latch switch and 2nd.
interlock relay control switch must open their contacts
first.
After that the contacts (COM-NC) of the monitor switch
can be closed.

6-2. When the oven door is closed, the contacts (COM-NC)

of the monitor switch must be opened. After that the
contacts of the 1st. latch switch and 2nd. interlock relay
control switch are closed.

6-3. When the oven door is opened and the contacts of the

1st. latch switch and 2nd. interlock relay remain closed.
The fuse M8A will blow, because the monitor switch is
closed and a short circuit is caused.

MEDIUM HIGH, MEDIUM, MEDIUM LOW, LOW
COOKING

When the microwave oven is preset for variable cooking
power, rated voltage is supplied to the power transformer
intermittently within a 32-second time base through the
relay contact which is coupled with the current-limiting relay.
The following levels of microwave power are given.

SETTING;

32 sec. ON

HIGH

24 sec. ON

MEDIUM HIGH

18 sec. ON

MEDIUM

12 sec. ON

MEDIUM LOW

6 sec. ON

LOW

NOTE: The ON/OFF time ratio does not exactly correspond

to the percentage of microwave power, because
approx. 2 seconds are needed for heating up the
magnetron filament.

8 sec. OFF

Approx. 70%

14 sec. OFF

Approx. 50%

20 sec. OFF

Approx. 30%

26 sec. OFF

Approx. 10%

4

FUNCTION OF IMPORTANT COMPONENTS

DOOR OPEN MECHANISM

The door is opened by pushing the open button on the
control panel, refer to the Figure D-1.
When the open button is pushed, the open button pushes up
the switch lever, and then the switch lever pushes up the
latch head. The latch heads are moved upward and re­leased from latch hook. Now the door will open.

LATCH HOOK

2ND. INTERLOCK

LATCH
HEADS

SWITCH
LEVER

Figure D-1. Door Open Mechanism

1ST. LATCH SWITCH AND 2ND. INTERLOCK RE­LAY CONTROL SWITCH

1. When the oven door is closed, the contacts (COM-NO)
must be closed.

2. When the oven door is opened, the contacts .(COM-NO)
must be opened.

MONITOR SWITCH

1. When the oven door is closed, the contacts (COM-NC)
must be opened.

2. When the oven door is opened, the contacts (COM-NC)
must be closed.

3. If the oven door is opened and the contacts (COM-NO)
of the 1st. latch switch and 2nd. interlock relay fail to
open, the fuse M8A blows simultaneously with closing
the contacts (COM-NC) of the monitor switch.

CAUTION: BEFORE REPLACING A BLOWN FUSE M8A

TEST THE 1ST. LATCH SWITCH, 2ND. IN­TERLOCK RELAY, 2ND. INTERLOCK RELAY
CONTROL SWITCH, MONITOR SWITCH AND
MONITOR RESISTOR FOR PROPER OPERA­TION.

MONITOR RESISTOR R 0.8Ω 20W

The monitor resistor prevents the fuse M8A bursting when
the fuse M8A blows due to the operation of the monitor
switch.

RELAY CONTROL
SWITCH

MONITOR 
SWITCH

1ST. LATCH
SWITCH

R-3A88

FUSE M8A

1. The fuse M8A blows when the contacts (COM-NO) of the
1st. latch switch and 2nd. interlock relay remain closed
with the oven door open and when the monitor switch
closes.

2. If the wire harness or electrical components are short­circuited, this fuse M8A blows to prevent an electric
shock or fire hazard.

THERMAL CUT-OUT TC 145˚C (MG)

This thermal cut-out protects the magnetron against over­heating. If the temperature goes up higher than 145˚C
because the fan motor is interrupted, the ventilation open­ings are blocked, the thermal cut-out will open and the line
voltage to the power transformer will be cut off and the
operation of the magnetron will be stopped.
The defective thermal cut-out must be replaced with new
one.

THERMAL CUT-OUT TC 145˚C (OVEN)

The thermal cut-out located on the top of the oven cavity is
designed to prevent damage to the oven 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 thermal cut-out remains closed. How­ever, when abnormally high temperatures are reached
within the oven cavity, the oven thermal cut-out will open at
145˚C, causing the oven to shut down. The defective
thermal cut-out must be replace with new one.

THERMAL CUT-OUT 95˚C (FAN MOTOR)

The thermal cut-out protect the fan motor against overheat­ing. If its temperature goes up higher than 95˚C because the
fan motor is locked or the ventilation operating are blocked,
the contacts of the thermal cut-out will open and switch off
the oven. When the oven cools itself down to 75˚C, the
contacts of the thermal cut-out will close again.

TURNTABLE MOTOR

The turntable motor drives the turntable roller assembly to
rotate the turntable.

FAN MOTOR

The fan motor drives a blade which draws external cool air.
This cool air is directed through the air vanes surrounding
the magnetron and cools the magnetron. This air is chan­nelled through the oven cavity to remove steam and va­pours given off from the heating foods. It is then exhausted
through the exhausting air vents at the oven cavity

5

R-3A88

SERVICING

WARNING TO SERVICE PERSONNEL

Microwave ovens contain circuitry capable of producing very high voltage and current, contact with any part of the
high voltage circuit will result in electrocution. High voltage capacitor, Power transformer, Magnetron, High voltage
rectifier assembly, High voltage harness.

REMEMBER TO CHECK 3D

1) Disconnect the supply.

2) Door opened, and wedged open.

3) Discharge high voltage capacitor.
WARNING: AGAINST THE CHARGE OF THE

HIGH-VOLTAGE CAPACITOR

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, of the
connecting lead of the high-voltage rectifier) against
the chassis with the use of an insulated screwdriver.

Sharp recommend that wherever possible fault-finding
is carried out with the supply disconnected. It may in,
some cases, be necessary to connect the supply after
the outer case has been removed, in this event carry out
3D checks and then disconnect the leads to the primary
of the power transformer. Ensure that these leads re­main isolated from other components and the oven
chassis. (Use insulation tape if necessary.) When the
testing is completed carry out 3D checks and reconnect
the leads to the primary of the power transformer.

REMEMBER TO CHECK 4R

1) Reconnect all leads removed from components during
testing.

2) Replace the outer case (cabinet).

3) Reconnect the supply.

4) Run the oven. Check all functions.

Microwave ovens should not be run 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 microwave timer for two (2) minutes. Set the
power level to HIGH and push the START button. When
the two minutes has elapsed (timer at zero) carefully
check that the water is now hot. If the water remains cold
carry out 3D checks and re-examine the connections 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 microwave leakage test carried out

TROUBLESHOOTING GUIDE

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.

IMPORTANT: If the oven becomes inoperative because

of a blown fuse M8A in the 1st. latch switch

- 2nd. interlock relay - monitor switch ­monitor resistor circuit, check the 1st. latch
switch, 2nd. interlock relay, 2nd. interlock
relay control switch, monitor switch and
monitor resistor before replacing the fuse
M8A.

6

R-3A88

CK = Check / RE = Replace

CONDITION

OFF
CONDITION

ON

CONDITION

TEST PROCEDURE

POSSIBLE CAUSE

AND

DEFECTIVE PARTS

PROBLEM

Home fuse blows when power
supply cord is plugged into wall
outlet.

FUSE M8A blows when power
supply cord is plugged into wall
outlet.

Display does not show anything
when power supply cord is plugged
into wall outlet.

Display does not operate prop­erly when STOP/CLEAR pad is
touched.

Oven lamp does not light at door
opened. (Display appears.)

Oven does not start when the
START pad is touched. (Display
appears)

Oven lamp does not light (Display
appears.)

Fan motor does not operate. (Dis­play appears.)

Turntable motor assembly does
not operate. (Display appears.)

Oven or any electrical parts does
not stop when cooking time is 0 or
STOP/CLEAR pad is touched.

Oven seems to be operating but
little or no heat is produced in
oven load. (Microwave power level
is set at HIGH)

Oven does not seems to be oper­ating properly when MEDIUM
HIGH, MEDIUM, MEDIUM LOW
or LOW is set. (Oven operates
properly at HIGH and when the
STOP/CLEAR pad is touched the
oven stops.)

Oven goes into cook cycle but
shuts down before end of cooking
cycle.

Oven stops as soon as the START
pad is touched.

ABCDE E EG FFH HI KLMN RECKCKRE CK CKCKCK CK

MAGNETRON

POWER TRANSFORMER

H.V. RECTIFIER ASSEMBLY

HIGH VOLTAGE CAPACITOR

1ST. LATCH SWITCH

2ND. INTERLOCK RELAY

CONTROL SWITCH

MONITOR SWITCH

MONITOR RESISTOR

THERMAL CUT-OUT 95˚C

THERMAL CUT-OUT 145˚C

FAN MOTOR

TURNTABLE MOTOR

FUSE M8A

TOUCH CONTROL PANEL

KEY UNIT

RELAY (RY-1, RY-2)

FOIL PATTERN ON P.W.B.

POWER SUPPLY CORD

SHORTED WIRE HARNESS

OPENED WIRE HARNESS

OVEN LAMP OR SOCKET

WALL OUTLET

MISADJUSTMENT SWITCH

HOME FUSE OR BREAKER

BLOCKED COOLING FAN

BLOCKED VENTILATION

7

R-3A88

PROCEDURE

LETTER

A MAGNETRON TEST

TEST PROCEDURES

COMPONENT TEST

NEVER TOUCH ANY PART IN THE CIRCUIT WITH YOUR HAND OR AN INSULATED TOOL
WHILE THE OVEN IS IN OPERATION.

CARRY OUT 3D CHECK.
Isolate the magnetron from high voltage circuit by removing all leads connected to filament terminal.
To test for an open circuit filament use an ohmmeter to make a continuity test between the magnetron

filament terminals, the meter should show a reading of less than 1 ohm.
To test for short filament to anode condition, connect ohmmeter between one of the filament terminals

and the case of the magnetron (ground). This test should be indicated an infinite resistance. If a low or
zero resistance reading is obtained then the magnetron should be replaced.

MICROWAVE OUTPUT POWER (IEC 705)

The following test procedure should be carried out with the microwave oven in a fully assembled
condition (outer case fitted). Microwave output power from the magnetron can be measured by way of
IEC 705, i.e. it can be measured by using water load how much it can be absorbed by the water load.
To measure the microwave output power in the microwave oven, the relation of calorie and watt is used.
When P(W) heating works for t(second), approximately P x t/4.187 calorie is generated. On the other
hand, if the temperature of the water with V(ml) rises ∆T (°C) during this microwave heating period, the
calorie of the water is V x ∆T.

The formula is as follows;

P x t / 4.187 = V x ∆ T P (W) = 4.187 x V x ∆T / t

Our condition for water load is as follows:

Room temperature..............around 20°C Power supply Voltage.........Rated voltage

Water load.........1000 g Initial temperature...........10±2°C Heating time.........49 sec.

P = 85 x ∆T

Measuring condition:

1. Container
The water container must be a cylindrical borosilicate glass vessel having a maximum material
thickness of 3 mm and an outside diameter of approximately 190 mm.

2. Temperature of the oven and vessel
The oven and the empty vessel are at ambient temperature prior to the start the test.

3. Temperature of the water
The initial temperature of the water is (10±2)°C.

4. Select the initial and final water temperature so that the maximum difference between the final water
temperature and the ambient temperature is 5˚C.

5. Select stirring devices and measuring instruments in order to minimize addition or removal of heat.

6. The graduation of the thermometer must be scaled by 0.1°C at minimum and accurate thermometer.

7. The water load must be (1000±5) g.

8. “t” is measured while the microwave generator is operating at full power. Magnetron filament heat­up time is not included.

NOTE:The operation time of the microwave oven is “t + 2” sec. 2 sec. is magnetron filament heat-up time.

Measuring method:

1. Measure the initial temperature of the water before the water is added to the vessel.
(Example: The initial temperature T1 = 11°C)

2. Add the 1 litre water to the vessel.

3. Place the load on the centre of the shelf.

4. Operate the microwave oven at HIGH for the temperature of the water rises by a value ∆ T of
(10 ± 2)˚C.

5. Stir the water to equalize temperature throughout the vessel.

8

PROCEDURE

LETTER

R-3A88

TEST PROCEDURES

COMPONENT TEST

6. Measure the final water temperature. (Example: The final temperature T2 = 21°C)

7. Calculate the microwave power output P in watts from above formula.

Initial temperature .................................................................................................. T1 = 11°C

Temperature after (49 + 2) = 51 sec. ..................................................................... T2 = 21°C

Temperature difference Cold-Warm.................................................................... ∆T1 = 10°C

Measured output power

The equation is “P = 85 x ∆T” ...................................................... P = 85 x 10°C = 850 Watts

JUDGMENT: The measured output power should be at least ± 15 % of the rated output power.

CAUTION: 1°C CORRESPONDS TO 85 WATTS REPEAT MEASUREMENT IF THE POWER IS

INSUFFICIENT.

1000g

1000g

1000g

T1˚C

B POWER TRANSFORMER TEST

WARNING: High voltages and large currents are present at the secondary winding and filament

winding of the power transformer. It is very dangerous to work near this part when
the oven is on. NEVER make any voltage measurements of the high-voltage
circuits, including the magnetron filament.

CARRY OUT 3D CHECKS.
Disconnect the leads to the primary winding of the power transformer. Disconnect the filament and

secondary winding connections from the rest of the HV circuitry. Using an ohmmeter, set on a low range,
it is possible to check the continuity of all three windings. The following readings should be obtained:

a. Primary winding ....................approx. 1.4 Ω

b. Secondary winding ...............approx. 98 Ω

c. Filament winding...................less than 1Ω

If the reading obtained are not stated as above, then the power transformer is probably faulty and should
be replaced.

T2˚C

Heat up for51 sec.

CARRY OUT 4R CHECKS.

C HIGH VOLTAGE RECTIFIER ASSEMBLY TEST

HIGH VOLTAGE RECTIFIER TEST
CARRY OUT 3D CHECKS.
Isolate the high voltage rectifier assembly from the HV circuit. The high voltage rectifier can be tested
using an ohmmeter set to its highest range. Connect the ohmmeter across the terminal B+C of the high
voltage rectifier and note the reading obtained. Reverse the meter leads and note this second reading.
The normal resistance is infinite in one direction and more than 100 kΩ in the other direction.

9

R-3A88

TEST PROCEDURES (CONT'D)

PROCEDURE

LETTER

D HIGH VOLTAGE CAPACITOR TEST

COMPONENT TEST

C

CARRY OUT 4R CHECKS.

B

HIGH VOLTAGE RECTIFIER

NOTE: FOR MEASUREMENT OF THE RESISTANCE OF THE RECTIFIER, THE BATTERIES OF THE

MEASURING INSTRUMENT MUST HAVE A VOLTAGE AT LEAST 6 VOLTS, BECAUSE
OTHERWISE AN INFINITE RESISTANCE MIGHT BE SHOWN IN BOTH DIRECTIONS.

CARRY OUT 3D CHECKS.
A. Isolate the high voltage capacitor from the circuit.

B. Continuity check must be carried out with measuring instrument which is set to the highest resistance

range.

C. A normal capacitor shows continuity for a short time (kick) and then a resistance of about 10M Ω after it has

been charged.
D. A short-circuited capacitor shows continuity all the time.
E. An open capacitor constantly shows a resistance about 10 MΩ because of its internal 10MΩ resistance.
F. When the internal wire is opened in the high voltage capacitor shows an infinite resistance.
G. The resistance across all the terminals and the chassis must be infinite when the capacitor is normal.
If incorrect reading are obtained, the high voltage capacitor must be replaced.

CARRY OUT

4R CHECKS.

E SWITCH TEST

CARRY OUT 3D CHECKS.
Isolate the switch to be tested and using an ohmmeter check between the terminals as described in the

following table.

Table: Terminal Connection of Switch

Plunger Operation COM to NO COM to NC

Released O.C. S.C.
Depressed S.C. O.C.

If incorrect readings are obtained, make the necessary switch adjustment or replace the switch.
CARRY OUT

4R CHECKS.

F THERMAL CUT-OUT TEST

CARRY OUT 3D CHECKS.
Disconnect the leads from the terminals of the thermal cut-out. Then using an ohmmeter, make a

continuity test across the two terminals as described in the table below.
CARRY OUT 4R CHECKS

Temperature of "ON" condition Temperature of "OFF" condition Indication ofohmmeter

Parts Name (closed circuit) (˚C) (open circuit) (˚C) (When room temperature

Thermal cut-out 145˚C This is not resetable type Above 145˚C Closed circuit.
Thermal cut-out 95˚C Below 75˚C Above 95˚C Closed circuit.

If incorrect readings are obtained, replace the thermal cut-out.

COM; Common terminal,
NO; Normally open terminal
NC; Normally close terminal
S.C.; Short,
O.C.; Open circuit

.Table: Thermal cut-out Test

is approx. 20˚C)

An open circuit thermal cut-out 145˚C (MG) indicates that the magnetron has overheated, this may be
due to resistricted ventilation, cooling fan failure or a fault condition within the magnetron or HV circuit.

An open circuit thermal cut-out 145˚C (OVEN) indicates that the foods in the oven may catch fire, this
may be due to over heating produced by improper setting of the cooking time or failure of the control
panel.

An open circuit thermal cut-out 95˚C (FAN) indicates that the fan motor winding has overheated, this
may be due to blocked ventilation or locked cooling fan.

10

TEST PROCEDURES (CONT'D)

R-3A88

PROCEDURE

LETTER

G MONITOR RESISTOR TEST

H MOTOR WINDING TEST

COMPONENT TEST

CARRY OUT 3D CHECKS.
Disconnect the leads from the monitor resist. Using an ohmmeter and set on a low range. Check between

the terminals of the monitor resistor.

The resistance of monitor resistor is approx. 0.8 ohms.
If incorrect readings are obtained, replace the monitor resistor.
CARRY OUT 4R CHECKS.

CARRY OUT 3D CHECKS.
Disconnect the leads from the motor.

Using an ohmmeter, check the resistance between the two terminals as described in the table below.

Table: Resistance of Motor
Motors Resistance
Fan motor Approximately 370 Ω
Turntable motor Approximately 16.08 kΩ

If incorrect readings are obtained, replace the motor. CARRY OUT 4R CHECKS

I BLOWN FUSE F M8A

CARRY OUT 3D CHECKS.

1. If the fuse M8A is blown, there could be shorts or ground in electrical parts or wire harness.
Check them and replace the defective parts or repair the wire harness.

2. If the fuse M8A is blown when the door is opened, check the 1st. latch switch, 2nd. interlock relay,
2nd. interlock relay control switch, monitor switch and monitor resistor.
If the fuse M8A is blown by incorrect door switching replace the defective switch(s) and the fuse M8A.

CARRY OUT 4R CHECKS.
CAUTION: ONLY REPLACE FUSE M8A WITH THE CORRECT VALUE REPLACEMENT.

J 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 cannot be performed with only a voltmeter
and ohmmeter.
In this service manual, the touch control panel assembly is divided into two units, Control Unit and Key
Unit, and troubleshooting by replacement is described according to the symptoms indicated.

1. Key Unit Note : Check key unit ribbon connection before replacement.
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.

2. Control Panel
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.

2-1 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.

11

R-3A88

TEST PROCEDURES (CONT'D)

PROCEDURE

LETTER

K KEY UNIT TEST

COMPONENT TEST

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) The figure of all digits flicker.

2-3 Other possible troubles 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.

If the display fails to clear when the STOP/CLEAR pad is depressed, first verify the flat ribbon is marking
good contact, verify that the door sensing switch (stop switch) operates properly; that is the contacts are
closed when the door is closed and open when the door is open. If the door sensing switch (stop switch)
is good, disconnecct 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 connecter). 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 marking momentary contact. If the control unit responds by
clearing with a beep the key unit is faulty and must be replaced. If the control unit does 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 key pad is at fault.

L RELAY TEST

CARRY OUT
Remove the outer case and check the voltage between Pin Nos. 3 and 5 of the 3 pin connector (A) on the

control unit with an A.C. voltmeter.
The meter should indicate 220 volts, if not check oven circuit.

RY1 and RY2 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 coil. If diode is good, control

G 8 G 7 G 6 G 5 G 4 G 3 G 2 G 1

G 9

G10

G11

G12

KEY UNIT

3D CHECKS.

54321

09876

EASY DEFROST

INSTANT

COOK

START

Sukiyaki

AUTO START

STOP / CLEAR

Mini pizza

SLOW COOK RICE COOK

POWER LEVEL

Tom Yum Kung

unit is defective.

STEAM MENU

REHEAT

HELP

12

TEST PROCEDURES (CONT'D)

R-3A88

PROCEDURE

LETTER

N PROCEDURES TO BE TAKEN WHEN THE FOIL PATTERN ON THE PRINTED WIRING BOARD

COMPONENT TEST

RELAY SYMBOL OPERATIONAL VOLTAGE CONNECTED COMPONENTS

RY1 APPROX. 25.0V D.C. Oven lamp / Turntable motor / Cooling fan motor
RY2 APPROX. 25.0V D.C. Power transformer

CARRY OUT 4R CHECKS.

(PWB) IS OPEN

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. If the foil pattern is open, follow the troubleshooting guide given
below for repair.

Problem: POWER ON, indicator does not light up.
CARRY OUT 3D CHECKS.

STEPS OCCURANCE CAUSE OR CORRECTION

1 The rated AC voltage is not present at Check supply voltage and oven power cord.

POWER terminal of CPU connector (CN-A).

2 The rated AC voltage is present at primary Low voltage transformer or secondary circuit defective.

side of low voltage transformer. Check and repair.

3 Only pattern at "a" is broken. *Insert jumper wire J1 and solder.

(CARRY OUT

4 Pattern at "a" and "b" are broken. *Insert the coil RCILF2003YAZZ between "c" and "d".

(CARRY OUT

3D CHECKS BEFORE REPAIR)

3D CHECKS BEFORE REPAIR)

NOTE: *At the time of making these repairs,

make a visual inspection of the varistor.
check for burned damage and examine
the transformer with a tester for the pres­ence of layer short-circuit (check primary
coil resistance). If any abnormal condi­tion is detected, replace the defective
parts.

CARRY OUT

4R CHECKS.

LOT NO.

c

(J2)

5

CN-A

(J1)

1

a

b

36

VRS1

d

13

R-3A88

TOUCH CONTROL PANEL ASSEMBLY

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 principal functions of these units and the signals com­municated among them 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 R10, R11, R12, R13,
R20, R21 and R22.
When a key pad is touched, a signal is completed through
the key unit and passed back to the LSI through R00, R01,
R02 and R03 to perform the function that was requested.

Control Unit

Control unit consists of LSI, power source circuit, synchro­nizing signal circuit, ACL circuit, buzzer circuit and indicator
circuit.

1) LSI

This LSI controls the key strobe signal, relay driving signal
for oven function and indicator signal.

7) Relay Circuit

To drive the magnetron, fan motor, turntable motor and
light the oven lamp.

8) Indicator Circuit

Indicator element is a Fluorescent Display.
Basically, a Fluorescent Display is triode having a cathode,
a grid and an anode. Usually, the cathode of a Fluorescent
Display is directly heated and the filament serves as
cathode.
The Fluorescent Display has 7-digits, 15-segments are
used for displaying figures.

2) Power Source Circuit

This circuit generates voltages necessary in the control
unit.

Symbol Voltage Application

VC -5V LSI(IC1)
VP -34V Fluorescent display tube : Grid

and anode voltage

VF1 2.2Vac Filament of fluorescent display

tube

VF2 (VF1 to VF2 voltage)

3) 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.

4) ACL Circuit

A circuit to generate a signals which resets the LSI to the
initial state when power is supplied.

5) Buzzer Circuit

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

6) Door Sensing Switch

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

14

DESCRIPTION OF LSI

LSI(IZA683DR)

The I/O signal of the LSI(IZA683DR) are detailed in the following table.

Pin No. Signal I/O Description

1 Vdisp IN

Anode (segment) of Fluorescent Display light-up voltage: -34V

Vp voltage of power source circuit input.

2 R00 IN

Signal coming from touch key.

When either one of G12 line keys on key matrix is touched, a corresponding signal out of R10

- R13, R20, R21 and R22 will be input into R00. When no key is touched, the signal is held
at "L" level.

3 R01 IN

Signal coming from touch key.

When either one of G11 line keys on key matrix is touched, a corresponding signal out of R10

- R13, R20, R21 and R22 will be input into R01. When no key is touched, the signal is held
at "L" level.

4 R02 IN

Signal coming from touch key.

When either one of G10 line keys on key matrix is touched, a corresponding signal out of R10

- R13, R20, R21 and R22 will be input into R02. When no key is touched, the signal is held
at "L" level.

5 R03 IN

Signal coming from touch key.

When either one of G9 line keys on key matrix is touched, a corresponding signal out of R10

- R13, R20, R21 and R22 will be input into R03. When no key is touched, the signal is held

at "L" level.
6 TEST IN Connected to VC.
7 RESET IN

Auto clear terminal.

Signal is input to reset the LSI to the initial state when power is applied. Temporarily set to “L”

level the moment power is applied, at this time the LSI is reset. Thereafter set at “H” level.
8 OSC1 IN

Internal clock oscillation frequency input setting.

The internal clock frequency is set by inserting the ceramic filter oscillation circuit with respect

to OSC1 terminal.
9 OSC2 OUT

Internal clock oscillation frequency control output.

Output to control oscillation input of OSC2.

10/11 GND/AVSS IN/IN Connected to VC.

12 AN0 IN

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

Door closed; "H" level signal.

Door opend; "L" level signal.

13-14 AN1-AN2 IN Terminal to change cooking constant.

15 R33 OUT

Oven lamp, turntable motor and cooling fan motor driving signal. (Square Waveform

: 50Hz)

To turn on and off shut-off relay. The square (50Hz) is delivered to the relay driving circuit and

cook relay control circuit.

16 P40 OUT

Magnetron high-voltage circuit driving signal.

To turn on and off the cook relay. In 100% power operation, the signals holds “L” level during

microwave cooking and “H” level while not cooking. In other cooking modes (10%, 30%, 50%,

70% power) the signal turns to “H” level and “L” level in repetition according to the power level.

17-19 R41-R43 OUT

Segment data signal.

Refer to the touch control panel circuit for the relationship between signals and indicators.

Normally, one pulse is output in every synchronized signal period, and input to the anode of

the fluorescent display.

20/21 AVCC/VCC IN/IN Connected to GND.

22 INT IN

Signal to synchronized with commercial source frequency(50Hz).

This is basic timing for time processing of LSI.

23-24 D1-D2 OUT

Segment data signal.

Refer to the touch control panel circuit for the relationship between signals and indicators.

Normally, one pulse is output in every synchronized signal period, and input to the anode of

the fluorescent display.

R-3A88

15

R-3A88

Pin No. Signal I/O Description

25 BUZZ OUT Signal to sound buzzer.

A: key touch sound (0.12 sec.).
B: Completion sound (2.4 sec.).

26-27 D4-D5 OUT

Segment data signal.

Refer to the touch control panel circuit for the relationship between signals and indicators.
Normally, one pulse is output in every synchronized signal period, and input to the anode of
the fluorescent display.

28 D6 OUT

Segment data signal.

Signal similar to P41.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R00-R03 terminal while one of
G8 line keys on key matrix is touched.

29-30 D7-D8 OUT

Digit selection signal.

Refer to the touch control panel circuit about the relation between signals and digits. Normally,
one pulse is output in every synchronized signal period, and input to the grid of the fluorescent
display.

31-34 R80-R83 OUT

Digit selection signal.

Refer to the touch control panel circuit about the relation between signals and digits. Normally,
one pulse is output in every synchronized signal period, and input to the grid of the fluorescent
display.

35 R10 OUT

Digit selection signal.

Refer to the touch control panel circuit about the relation between signals and digits. Normally,
one pulse is output in every synchronized signal period, and input to the grid of the fluorescent
display.

36 R11 OUT

Segment data signal.

Signal similar to P41.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R00-R03 terminal while one of
G7 line keys on key matrix is touched.

37 R12 OUT

Segment data signal.

Signal similar to P41.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R00-R03 terminal while one of
G6 line keys on key matrix is touched.

38 R13 OUT

Segment data signal.

Signal similar to P41.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R00-R03 terminal while one of
G5 line keys on key matrix is touched.

39 R20 OUT

Segment data signal.

Signal similar to P41.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R00-R03 terminal while one of
G4 line keys on key matrix is touched.

40 R21 OUT

Segment data signal.

Signal similar to P41.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R00-R03 terminal while one of
G3 line keys on key matrix is touched.

41 R22 OUT

Segment data signal.

Signal similar to P41.

Key strobe signal.

Signal applied to touch-key section. A pulse signal is input to R00-R03 terminal while one of
G2 line keys on key matrix is touched.

42 R23 OUT

Segment data signal.

Signal similar to P41.

16

SERVICING

R-3A88

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. and some­times it is not fully protected by the built-in protection circuit.
In order to protect CMOS LSI.

1) When storing and transporting, thoroughly wrap them in
aluminium foil. Also wrap all PW boards containing them in
aluminium foil.

2) When soldering, ground the technician as shown in the
figure and use grounded soldering iron and work table.

approx. 1M ohm

2. Shapes of Electronic Components

Transistor
2SA933S
DTA143ES
KRA101M

B

C

E

KRC243M

3. 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 supply to the touch control panel is available either
from the power line of the oven itself or from an external
power source.

(1) Servicing the touch control panel with power supply of

the oven:
CAUTION:
THE HIGH VOLTAGE TRANSFORMER OF THE MICRO­WAVE OVEN IS STILL LIVE DURING SERVICING
PRESENTS A HAZARD.

Therefore, when checking the performance of the touch
control panel, put the outer cabinet on the oven to avoid
touching the high voltage transformer, or unplug the primary
terminal (connector) of the high voltage transformer to turn
it off; and the end of such connector must be insulated with
an insulating tape. After servicing, be sure to replace the
leads to their original locations.

A. 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.

B. 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 sensor­related controls of the touch control panel, checking them
is possible if dummy resistor(s) with resistance is equal to
that of the controls are used.

(2) Servicing the touch control panel with power supply

from an external power source:

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 brings
about 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).

4. Servicing Tools

Tools required to service the touch control panel assembly.

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

2) Oscilloscope: Single beam, frequency range: DC-10MHz
type or more advanced model.

3) Others: Hand tools

5. Other Precautions

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

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

3) Attach connectors, electrolytic capacitors, etc. to PWB,
making sure that all connections are tight.

4) Be sure to use specified components where high precision
is required.

17

R-3A88

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE

WARNING: Avoid possible exposure to microwave energy. Please follow the instructions below before

operating the oven.

1. Disconnect oven from power supply.

2. Make sure that a definite” click” can be heard when the
microwave oven door is unlatched. (Hold the door in a
closed position with one hand, then push the door open
button with the other, this causes the latch leads to rise,
it is then possible to hear a “click’ as the door switches
operate.)

3. Visually check the door and cavity face plate for damage

1. Door does not close firmly.

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

3. The door gasket or seal or 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 generating
and transmission assembly.

7. There is visible damage to the oven.

(dents, cracks, signs of arcing etc.).

Do not operate the oven:
Carry out any remedial work that is necessary before
operating the oven.
Do not operate the oven if any of the following conditions
exist;

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.

Please refer to ‘OVEN PARTS, CABINET PARTS, CONTROL PANEL PARTS, DOOR PARTS’, when carrying out any of
the following removal procedures:

OUTER CASE REMOVAL

To remove the outer case proceed as follows.

1. Disconnect oven from power supply.

2. Open the oven door and wedge it open.

3. Remove the six (6) screws from rear and along the right
side edge of case.

4. Slide the entire case back about 3cm to free it from
retaining clips on the cavity face plate.

5. Lift the entire case from the unit.

6. Discharge the H.V. capacitor before carrying out any
further work.

7. Do not operate the oven with the outer case removed.

N.B.; Step 1, 2 and 7 form the basis of the 3D checks.

CAUTION: DISCHARGE HIGH VOLTAGE CAPACITOR

BEFORE TOUCHING ANY OVEN COMPONENT
OR WIRING.

MAGNETRON REMOVAL

Removal

1. CARRY OUT 3D CHECKS.

2. Disconnect wire leads from magnetron.

3. Remove the two (2) screws holding chassis support to
oven cavity front plate and magnetron.

4. Remove the chassis support from oven.

5. Carefully remove the two (2) screws holding magnetron
to waveguide flange.

6. Lift up magnetron with care so that magnetron antenna
is not hit by any metal object around antenna.

7. Now, the magnetron is free.

Re-install

1. Re-install the magnetron to waveguide flange with the
two (2) screws diagonally as shown in Figure C-1.

2. Re-install the chassis support to oven cavity front plate
and magnetron with the two (2) screws.

3. Reconnect the wire leads to the magnetron. Refer to
"PICTORIAL DIAGRAM".

POWER TRANSFORMER REMOVAL

1. CARRY OUT 3D CHECKS.

2. Disconnect wire leads from power transformer,

4. Re-install outer case and check that the oven is operating
properly.

CAUTION: WHEN REPLACING MAGNETRON, BE SURE

THE R.F. GASKET IS IN PLACE AND MOUNT­ING SCREWS ARE TIGHTENED SECURELY

SCREWS

MAGNETRON

WAVEGUIDE
FLANGE

Figure C-1. Magnetron replacement

magnetron and capacitor terminals.

3. Remove four (4) screws holding transformer to bottom

18

R-3A88

plate right.

4. Remove transformer from bottom plate right.

5. Remove the one (1) terminal insulator from filament lead
(longer one) of power transformer.

Re-install

1. Insert tube into filament lead (longer one) of power
transformer.

2. Install the terminal insulator to receptacle of filament
lead (longer one) of power transformer.

TERMINAL INSULATOR REPLACEMENT

1. Open covers of the terminal insulator by using small flat
type screw driver.

2. Remove the receptacle from the terminal insulator.

3. Now, the terminal insulator is free.

Terminal 
insulator

Flat type
screw driver

HIGH VOLTAGE RECTIFIER AND HIGH VOLTAGE CAPACITOR REMOVAL

3. Rest transformer on the bottom plate right with its primary
terminals toward the oven face plate.

4. Secure transformer with four screws to bottom plate
right.

5. Re-connect wire leads (primary and high voltage) to
power transformer and filament leads of transformer to
magnetron and high voltage capacitor. Refer to
"PICTORIAL DIAGRAM".

6. Re-install outer case and check that oven is operating
properly.

Installation

1. Insert the receptacle into terminal insulator.

2. Close covers of the terminal insulator, as shown illustlated
below.

COVERS

RECEPTACLE

1. CARRY OUT 3D CHECKS.

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

3. Remove one (1) screw holding capacitor holder to oven
cavity rear plate.

4. Remove one (1) screw holding high voltage rectifier
assembly to capacitor holder.

5. Disconnect rectifier terminal from capacitor.

6. Now, high voltage rectifier assembly is free.

POSITIVE LOCK® CONNECTOR REMOVAL

1. CARRY OUT 3D CHECKS.

2. Pushing the lever of positive lock® connector.

3. Pull out the positive lock® connector.
CAUTION: WHEN YOU (SERVICE ENGINEERS) CON-

NECT THE POSITIVE LOCK® CONNECTORS
TO THE TERMINALS, CONNECT THE POSI­TIVE LOCK® SO THAT THE LEVER FACE
YOU (SERVICE ENGINEERS).

CONTROL PANEL ASSEMBLY REMOVAL

7. Disconnect wire leads from capacitor and remove
capacitor holder.

8. Now, high voltage capacitor is free.

CAUTION: WHEN REPLACING HIGH VOLTAGE

RECTIFIER AND HIGH VOLTAGE CAPACITOR,
GROUND SIDE TERMINAL OF THE HIGH VOLTAGE
RECTIFIER MUST BE SECURED FIRMLY WITH A
GROUNDING SCREW.

Terminal

Positive lock®
connector

Lever

1

Push

2

Pull down

Figure C-2. Positive lock® connector

1. CARRY OUT 3D CHECKS.

2. Disconnect wire leads from panel components.

3. Release one (1) nail holding the control panel assembly
to the oven flange.

4. Remove control panel assembly and slide upward.

5 . Now, individual components can be removed.
NOTE: 1. Before attaching a new key sheet, remove

remaining adhesive on the control panel frame

surfaces completely with a soft cloth soaked in
alcohol.

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

3. Stick the key sheet firmly to the control panel
frame by rubbing with soft cloth not to scratch.

19

R-3A88

TURNTABLE MOTOR REMOVAL

1. Disconnect oven from power supply.

2. Remove turntable and turntable support from oven cavity.

3. Lay the oven on it's backside. Remove the turntable
motor cover by snipping off the material in four corner.

4. Where the corners have been snipped off bend corner
areas flat. No sharp edge must be evident after removal
of the turntable motor cover.

5. Disconnect wire leads from turntable motor.
(See "Positive lock connector removal")

COOLING FAN MOTOR REMOVAL

1. CARRY OUT 3D CHECKS.

2. Disconnect the wire leads from the fan motor, thermal
cut-out (FAN) and magnetron.

3. Remove two (2) screws holding the chassis support to
oven cavity front plate and magnetron. And remove
chassis support.

4. Remove two (2) screws holding the magnetron to
waveguide flange. And remove the magnetron.

5. Remove one (1) screw holding the fan duct assembly to
oven cavity.

6. Release the fan duct assembly from the oven cavity.

7. Remove one (1) screw holding the thermal cut-out angle
to the fan motor.

8. Remove the fan blade from the fan motor shaft according
the following procedure.

1) Hold the edge of the rotor of the fan motor by using a pair
of grove joint pliers.

CAUTION:
* Make sure that any pieces do not 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.

2) Remove the fan blade from the shaft of the fan motor by
pulling and rotating the fan blade with your hand.

3) Now, the fan blade will be free.

CAUTION:
* Do not use this removed fan blade again because the

hole (for shaft) of it may become bigger than a
standard one.

Coil

Groove joint pliers

6. Remove two (2) screws holding turntable motor to oven
cavity.

7. Now the turntable motor is free.

8. After replacement use the one (1) screw to fit the
turntable motor cover.

NOTE: The one (1) screw to fit the turntable motor cover

should be XOTSD40P12000, XOTSD40P10000 or
XOTSD40P08000.

9. Remove the two (2) screws holding the fan motor to the
fan duct.

10.Now, the fan motor is free.

INSTALLATION

1. Install the fan motor to the fan duct with the two (2)
screws.

2. Install the fan blade to the fan motor shaft according the
following procedure.

1) Hold the center of the bracket which supports the shaft
of the fan motor on the flat table.

2) Apply the screw lock tight into the hole (for shaft) of the
fan blade.

3) Install the fan blade to the shaft of fan motor by pushing
the fan blade with a small, light weight, ball peen hammer
or rubber mallet.

CAUTION:
* Do not hit the fan blade strongly when installed

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.

3. Install the thermal cut-out angle to the fan motor with one
(1) screw.

4. Catch two holes of fan duct on two tabs of the waveguide
flange.

5. Install the fan duct assembly to the oven cavity with the
one (1) screw.

6. Install the magnetron to waveguide flange with two (2)
screws.

7. Install one (1) tab of the chassis support to oven cavity
front plate and install another tab of it to rear plate. And
then screw chassis support to oven cavity front plate and
magnetron with two (2) screws.

8. Connect the wire leads to the fan motor, magnetron and
thermal cut-out (FAN), referring to the pictorial diagram.

Shaft

Stator

Gap
Bracket

Rotor

Shaft

Axis

Stator

Rotor

These are the position
where should be
pinched with pliers

Table

Center of
bracket

Side ViewRear View

20

OVEN LAMP AND LAMP SOCKET REMOVAL

15 mm

Connector
CE-230

Blue wire lead of power supply cord

Wire lead of the 
main wire harness

Conductor: 
Stripped portion


Connector
CE-230

1. CARRY OUT 3D CHECKS.

2. 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.

3. Bend the tab of the oven cavity holding the lamp socket.

4. Lift up the oven lamp socket.

5. Now, the oven lamp socket is free.

POWER SUPPLY CORD REPLACEMENT

R-3A88

Oven lamp
socket

Terminal

Wire lead

Terminal hole

Flate type small
screw driver

Figure C-3. Oven lamp socket

Removal

1. CARRY OUT 3D CHECKS.

2. Remove the one (1) screw holding the green/yellow wire
to the bottom plate right.

3. Disconnect the brown wire lead of the power supply cord
from the fuse holder.

4. Cut away the connector.

5. Release the power supply cord from the rear cabinet.

6. Now, the power supply cord is free.

Re-install

1. Insert the moulding cord stopper of power supply cord
into the square hole of the rear cabinet.

2. Install the earth wire lead of power supply cord to the
bottom plate rirgt with one (1) screw and tight the screw.

3. Connect the brown wire lead of power supply cord to the
fuse holder correctly, referring to the Pictorial Diagram.

4. Strip the blue wire lead of the power supply cord and
white wire lead of the main wire harness for 15mm lengh
from their end.

1ST. LATCH SWITCH, 2ND. INTERLOCK RERAY CONTROL SWITCH AND MONITOR SWITCH REMOVAL

1. CARRY OUT 3D CHECKS.

2. Disconnect wire leads from the switches.

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

4. Remove latch hook assembly from oven flange.

5. Push outward on the two (2) retaining tabs holding each
switch in place.

6. Switches are now free. At this time switch lever will be
free, do not lose it.

Re-install

1. Re-install each switch and switch lever in its place.

1ST. LATCH SWITCH, 2ND. INTERLOCK RERAY CONTROL SWITCH AND MONITOR SWITCH

5. Wind the conductor of the blue wire lead of the power
supply cord and the conductor of the wire lead of the
main wire harness each other.

6. Insert them into the connector. And clamp it.

7. CARRY OUT 4R CHECKS.

Figure C-4. Power supply cord replacement

The 1st. latch switch and monitor switch are in the lower
position and 2nd. interlock relay control switch is in the
upper position.

2. Re-connect wire leads to each switch.
Refer to pictorial diagram.

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.

If each switch does not operate properly due to a
misadjustment, the following adjustment should be made.

1. Loosen the two (2) screws holding latch hook to the oven

ADJUSTMENT

cavity front flange.

2. With door closed, adjust 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 hook

21

R-3A88

should be less than 0.5mm. The vertical position of the
latch hook should be adjusted so that the 1st. latch
switch 2nd. interlock relay control switch are activated
with the door closed. The horizontal position of the latch
hook should be adjusted so that the monitor switch is
activated with the door closed.

3. Secure the screws with washers firmly.

4. Check the operation of all switches. If any switch has not
activated with the door closed, loosen screw and adjust
the latch hook position.

After adjustment, check the following.

1. In and out play of door remains less than 0.5mm when in
the latched position. First check upper position of latch
hook, pushing and pulling upper portion of door toward
the oven face. Then check lower portion of the latch
hook, pushing and pulling lower portion of the door
toward the oven face. Both results (play in the door)
should be less than 0.5mm.

2. The 1st. latch switch and 2nd. interlock relay control
switch interrupt the circuit before the door can be opened.

DOOR REPLACEMENT

3. Monitor switch contacts close when door is opened.

4. Re-install outer case and check for microwave leakage
around door with an approved microwave survey meter.
(Refer to Microwave Measurement Procedure.)

LATCH HOOK

2ND. INTERLOCK
RELAY CONTROL
SWITCH

MONITOR 
SWITCH

1ST. LATCH
SWITCH

SWITCH
LEVER

LATCH
HEADS

Figure C-5. Latch Switch Adjustments

REMOVAL

1. Disconnect oven from power supply.

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

3. Insert an putty knife (thickness of about 0.5mm) into the
gap between the choke cover and corner portion of door
frame as shown Figure C-6 to free engaging parts.

4. Try the principles of the lever and lift up the choke cover
by inserting a putty knife as shown Figure C-6.

5. Release choke cover from door panel.

6. Now choke cover is free.

7. Release two (2) pins of door panel from two (2) hole of
upper and lower oven hinges by lifting up.

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

9. Remove the two (2) screws holding the door panel to the
door frame.

10.Release door panel from nine (9) tabs of door frame by
sliding door panel downward.

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 by releasing two
(2) tabs.

17.Now, door screen is free.

9

8

7

6

5

Choke Cover

4

10

11

12

1



2

3

Putty Knife

Door frame

Figure C-6. Door Disassembly

RE-INSTALL

1. Re-install door screen to door frame by fitting two (2) tabs
of door frame to two (2) holes of door screen.

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

3. Re-install door panel to door frame by fitting nine (9) tabs
of door frame to nine (9) holes of door panel.

4. Hold the door panel to the door frame with two (2)
screws.

5. Put sealer film on door panel. Refer to "Sealer Film"
about how to handle new one.

6. Catch two (2) pins of door panel on two (2) hole of upper
and lower oven hinges.

7. Re-install choke cover to door panel by pushing.

22

R-3A88

Note: After any service to the door;
(A) Make sure that door sensing switch and secondary

interlock switch are operating properly. (Refer to
chapter "Test Procedures".).

(B) An approved microwave survey meter should be

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

After any service, make sure of the following :

1. Door latch heads smoothly catch latch hook through
latch holes and that latch head goes through center of
latch hole.

2. Deviation of door alignment from horizontal line of cavity
face plate is to be less than 1.0mm.

3. Door is positioned with its face pressed toward cavity
face plate.

4. Check for microwave leakage around 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 oven cavity during cook
cycle. This function does not require that door be air­tight, moisture (condensation)-tight or light-tight.
Therefore, occasional appearance of moisture, light
or sensing of gentle warm air movement around
oven door is not abnormal and do not of themselves,
indicate a leakage of microwave energy from oven
cavity.

SEALER FILM

Installation

1. Put the adhesive tape on the backing film of the sealer
film as shown in Fig. C-8.

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

Adhesive tape

Figure C-8. Sealer film

PIN

UPPER 
OVEN HINGE

DDOR PANEL

CHOKE 
COVER

LOWER 
OVEN 

PIN

HINGE

Figure C-7. Door Replacement

23

R-3A88

MICROWAVE MEASUREMENT

After adjustment of door latch switches, monitor switch
and door are completed individually or collectively, the
following leakage test must be performed with a survey
instrument and it must be confirmed that the result meets
the requirements of the performance standard for micro­wave oven.

REQUIREMENT

The safety switch must prevent microwave radiation emis­sion in excess of 5mW/cm2 at any point 5cm or more from
external surface of the oven.

PREPARATION FOR TESTING:

Before beginning the actual test for leakage, proceed as
follows;

1. Make sure that the test instrument is operating normally
as specified in its instruction booklet.
Important:
Survey instruments that comply with the requirement for
instrumentations as prescribed by the performance
standard for microwave ovens must be used for testing.

Recommended instruments are:
NARDA 8100
NARDA 8200
HOLADAY HI 1500
SIMPSON 380M

2. Place the oven tray into the oven cavity.

3. Place the load of 275 ± 15ml of water initially at 20 ±
5˚C in the centre of the oven tray. The water container
should be a low form of 600 ml beaker with inside
diameter of approx. 8.5cm and made of an electrically
non-conductive 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.

4. Close the door and turn the oven ON with the timer set
for several minutes. If the water begins to boil before the
survey is completed, replace it with 275ml of cool water.

5. Move the probe slowly (not faster that 2.5cm/sec.)
along the gap.

6. The microwave radiation emission should be measured
at any point of 5cm or more from the external surface of
the oven.

mW cm

mW cm

SHARP

2

2

Microwave leakage measurement at 5 cm distance

24

SCHEMATIC

NOTE: CONDITION OF OVEN

1.DOOR CLOSED

2.CLOCK APPEARS ON DISPLAY

THERMAL

CUT-OUT

FUSE

M8A

145˚(MG)

THERMAL

CUT-OUT

145˚C 

(OVEN)

R-3A88

NOTE: " " indicates components with potentials above 250V.

BRN

50Hz

˜

220 V

G-Y

EARTH

BLU

THERMAL CUT-OUT
95˚C (FAN)

SCHEMATIC

NOTE: CONDITION OF OVEN

1. DOOR CLOSED

2. COOKING TIME PROGRAMMED

3. START KEY TOUCHED

COM.

A5

A3

2ND. INTERLOCK RELAY
CONTROL SWITCH

B1

1ST. LATCH
SWITCH

2ND. 

INTERLOCK 

RELAY

N.O.

RY-2

CONTROL

UNIT

B2

A1

RY-1

OL

FM

OVEN LAMP

TTM

FAN MOTOR

TURNTABLE MOTOR

Figure O-1. Oven Schematic-OFF Condition

MONITOR

RESISTOR

0.8/20W

MONITOR SWITCH

POWER TRANSFORMER

CAPACITOR

1.07µ

AC2100V

MAGNETRON

H.V. RECTIFIER

BRN

50Hz

˜

220 V

BLU

THERMAL

FUSE

CUT-OUT

M8A

G-Y

EARTH

THERMAL CUT-OUT
95˚C (FAN)

THERMAL

CUT-OUT

145˚C 

145˚(MG)

(OVEN)

COM.

A5

A3

2ND. INTERLOCK RELAY
CONTROL SWITCH

2ND. 

INTERLOCK 

B1

1ST. LATCH
SWITCH

RELAY

RY-2

N.O.

CONTROL

B2

UNIT

A1

RY-1

OL

OVEN LAMP

FM

Figure O-2. Oven Schematic-Cooking Condition

25

TTM

FAN MOTOR

TURNTABLE MOTOR

MONITOR

POWER TRANSFORMER

RESISTOR

0.8/20W

MONITOR SWITCH

CAPACITOR

1.07µ

AC2100V

MAGNETRON

H.V. RECTIFIER

R-3A88

1

A

B

OVEN LAMP 

AND SOCKET

C

THERMAL CUT-OUT

RED

WHT

BLUE MARK

NOTE:

Live (RED) wire must be

connected to the terminal

with blue mark on the

oven light socket.

BLKBLK

(OVEN)

2

MAGNETRON

HIGH VOLTAGE COMPONENTS

3

RECTIFIER
H.V.

HIGH 

VOLTAGE

HIGH VOLTAGE

WIRE B

WHT

45

CORD

POWER

CAPACITOR

HIGH VOLTAGE

TRANSFORMER

RED

RED

WHT

SUPPLY

NEUTRAL

RED

BLU

BRN

FUSE

M8A

G

LIVE

GRY

EARTH

/

Y

BRN

BLK

ORG

TURNTABLE

MOTOR

6

A

B

C

D

E

F

G

BLK

RED

FAN MOTOR

GRY

N.O.

2ND INTERLOCK

RELAY CONTROL

SWITCH

WHT

GRY

GRN

COM.

CN-B

GRN

2

GRY

1

THERMAL CUT-OUT

(FAN)

GRN

GRN

CN-A

WHT

WHT

WHT

GRY

ORG
12345

THERMAL CUT-OUT

(MAGNETRON)

GRY

WHT

GRY

N.C.

COM.

BLKRED

MONITOR

SWITCH

WHT

NO

1ST 

GRY

LATCH

SWITCH

GRY

MONITOR

RESISTOR

WHT

GRY

COM.

D

RED

E

Figure S-1. Pictorial Diagram

F

G

H

1

LSI

CONTROL UNIT

CN-G

2

RY1

CN-B

21

51

3

26

CN-A

RED

RY2

BLK

45

H

6

R-3A88

1

A

B

FLUORESCENT DISPLAY TUBE

COOK KG DEF HELP

C

D

CONTROL UNIT

Q1

C7

0.1µ/50V

E

C6

47µ/16V

-

+

F

R6 12 1/2W

D2

D1 S1NB10

5

6

G

T1

3

1

2

VRS1

F
F
P
P
P
P
P

P
P
1
2
3
4
5
6
7
P
P
P
P
P
P
P
P
F
F

2SA933

1K
R4

C4

+

+

4

d

1
1
1
2
3
4
5

6
7
G
G
G
G
G
G
G

8
9

10
11

12
13
14
15

2
2

1

28

-

-

2

R75 100K
R74 100K
R73 100K

(A)

(B)

(C)

C5

4.7K
R5

HZ4C3
ZD2

VC

C3 47µ/16V

R3

820

1/2W

R7 150

R2

820

1/2W

C2 330µ/35V

C1 0.1µ/50V

0.01µ/25V
C10

R11 56K

R10 47K

a
b

c

(J1)

3

R22

R21

R20

R13

R23

42

1

Vdsp

R00

40

R01

R02

5

R03

R12

TEST

R11

RST

R10

35

OSC1

SP40

R41 3.3K

+

Q20

KRA101M

+

D20 D21

J35

510

RY1

(J2)

R83

R82

10

GND

OSC2

1M
R60

CF1 4MHz

(D)

-

10µ/35V
C21

-

Q21

KRC243M

J27 150

RY2

D8D7D6D5D4

R81

R80

30

IC1 IZA683DR

15

R33

AN0

AN1

AN2

AVSS

C20 0.1µ/50V

Q22

DTA143ES

R40

R41

45

D56

D55

D54

STEAM MENU

Mini pizza

POWER LEVEL

SLOW COOK

REHEAT

RICE COOK

D53

D52

Sukiyaki

D51

EASY DEFROST

0987 6

G10

BUZZ

25

D50

5432 1

G 8 G 7 G 6 G 5 G 4 G 3 G 2 G 1

D2

D1

INT

22

R40 1K

G 9

(D)

20

R42

R43

AVCC

21

VCC

C50

330p x 4

R72 4.7K

Q72Q71Q70

R71 4.7K

(A) (B) (C)

R70 4.7K

R50

150K x 4

R51 15K

Q70~Q72

2SA933

R52 15K

VC

(J6)

C30

R31 4.7K

R30 15K

(J5)

(J3) (J4)

D30

D22

Note : IF NOT SPECIFIED, 1/4W ± 5%

6

KEY UNIT

HELP

Tom Yum Kung

STOP/CLEAR

AUTO START

COOK

START

INSTANT

G12

G11

R53 15K

R54 15K

Figure S-2. Contrl Panel Circuit

IF NOT SPECIFIED, 1SS270A

IF NOT SPECIFIED, 0.01µF/16V

A

B

C

D

E

F

G

A3

H

1

AC220V

50Hz

A5

A1

FAN MOTOR

TURNTABLE

MOTOR 

2

NO

COM

OVEN LAMP

POWER

TRANSFORMER

3

27

B2

B1

DOOR

SWITCH

45

H

6

R-3A88

1

A

B

C

D

E

F

G

2

FLR. DISPLAY

TAPE

5

19

20

21

22

23

24

C50

R10

(D3)

(R81)

1

R51
R52
R53

R54
B

ZD2

R4

E

31

Q1

DOOR

R50

R11

C1

(D6)

1

CN - G

12

D57
(D56)
(D55)

D54
D53
D52
D51
D50

(D5)

(D4)

D1

BFB

F

RY2

SMCA

SATL

3

QKITPB014MRE0

10 15 20 25 281

10

11

12

13

14

15

16

17

18

R60

CE1

C5

R5

B

Q22

C4

C3

32

33 34

SW

2

CN - B

C10

LOT NO.

POWER FM TTM OL

5

CN - A

(J1)

(J2)

T1

IC1

R30

30

1

9

(R80)

(J4)
(J6)

C30

R31



29

E

D30

D22

C2

36

VRS1

2

S2 S1

6

5

45

DIP

6

3

4

1

25

(J3)

(J5)

Q21

E

1

7

8

2142

R71

21

28

C20

B

C21

P

R72

27 35

Q20

2

R73

R6

R74
R75

B

RY1

D20

1

C7

R40

C6

34

Q72

26

SP40

(R7)

(J7)

D2

E

Q71

E

Q70

R41

B
B
B

R70

R3 R2

E

6

A

B

C

D

E

F

G

H

1

D21

Figure S-3. Printed Wiring Board

2

3

28

45

H

6

PARTS LIST

Note: The parts marked "∆" may cause undue microwave exposure.

The parts marked "*" are used in voltage more than 250V.

REF. NO. PART NO. DESCRIPTION Q'TY CODE

ELECTRICAL PARTS

1- 1 QSW-MA110WRE0 1st. latch and 2nd. Iinterlock relay control switches 2 AK
1- 2 QSW-MA111WRE0 Monitor switch 1 AK

∆

1- 3 RV-MZA197WRE0 Magnetron 1 BN

*

1- 4 RTHM-A080WRE0 Thermal cut-out 145˚C 2 AP
1- 5 FH-DZA047WRK0 High voltage rectifier assambly 1 AQ

*

1- 6 RC-QZA172WRE0 High voltage capacitor 1 AY

*

1- 7 RMOTEA265WRE0 Cooling fan motor 1 AZ
1- 8 RTHM-A072WRE0 Thermal cut-out 95˚C 1 AM
1- 9 QACC-A065WRE0 Power supply cord 1 AS
1-10 QFS-CA010WRE0 Fuse (M8A) 1 AE
1-11 QFSHDA019WRE0 Fuse holder 1 AH
1-12 QSOCLA022WRE0 Oven lamp socket 1 AG
1-13 RLMPTA069WRE0 Oven lamp 1 AK
1-14 RMOTDA169WRE0 Turntable motor 1 AW
1-15 RR-WZA003WRE0 Monitor resistor 0.8Ω 20W 1 AG
1-16 RTRN-A480WRE0 Power transformer 1 BP

*

1-17 QPLGAA018WRE0 AC plug 1 AL

CABINET PARTS

2- 1 GCABUA522WRT0 Outer case cabinet 1 AT
2- 2 FDAI-A171WRY0 Bottom plate right 1 AT
2- 3 GDAI-A261WRW0 Bottom plate left 1 AP
2- 4 GLEGPA019WRE0 Foot 4 AD

CONTROL PANEL PARTS

3- 1 CPWBFA684WRK0 Control unit 1 BM
3- 1A QCNCMA234DRE0 3-pin connector (CN-A) 1 AC
3- 1B QCNCMA275DRE0 2-pin connector (CN-B) 1 AB
3- 1C QCNCWA057DRE0 12-pin connector (CN-G) 1 AF
3- 1D RV-KXA069DRE0 Fluorescent display tube 1 AX
C1 RC-KZA132DRE0 Capacitor 0.1uF 50V 1 AC
C2 VCEAB31VW337M Capacitor 330uF 35V 1 AC
C3 VCEAB31CW476M Capacitor 47uF 16V 1 AA
C4-5 VCKYD11CY103N Capacitor 0.01uF 16V 2 AH
C6 VCEAB31CW476M Capacitor 47uF 16V 1 AA
C7 RC-KZA132DRE0 Capacitor 0.1uF 50V 1 AC
C10 VCKYB11EX103N Capacitor 0.01uF 25V 1 AA
C20 VCEAB31HW104M Capacitor 0.1uF 50V 1 AB
C21 VCEAB31VW106M Capacitor 10uF 35V 1 AB
C30 VCKYD11CY103N Capacitor 0.01uF 16V 1 AH
C50 RMPTEA009DRE0 Capacitor array 330pF x 4 1 AE
CF1 RCRS-A012DRE0 Ceramic resonator (CST4.00MGW) 1 AD
D1 RSRCDA013DRE0 Diode bridge (S1NB10) 1 AG
D2 VHD1SS270A/-1 Diode (1SS270ATA) 1 AA
D20-22 VHD1SS270A/-1 Diode (1SS270ATA) 3 AA
D30 VHD1SS270A/-1 Diode (1SS270ATA) 1 AA
D50-56 VHD1SS270A/-1 Diode (1SS270ATA) 7 AA
IC1 RH-IZA683DRE0 LSI 1 AU
Q1 VS2SA933S//-3 Transistor (2SA933S) 1 AB
Q20 VSKRA101M//-3 Transistor (KRA101M) 1 AB
Q21 VSKRC243M//-3 Transistor (KRC243M) 1 AB
Q22 VSDTA143ES/1B Transistor (DTA143ES) 1 AB
Q70-72 VS2SA933S//-3 Transistor (2SA933S) 3 AB
R2-3 VRD-B12HF821J Resistor 820 ohm 1/2W 2 AD
R4 VRD-B12EF102J Resistor 1.0k ohm 1/4W 1 AA
R5 VRD-B12EF472J Resistor 4.7k ohm 1/4W 1 AA
R6 VRD-B12HF120J Resistor 12 ohm 1/2W 1 AB
R7 VRD-B12EF151J Resistor 150 ohm 1/4W 1 AA
R10 VRD-B12EF473J Resistor 47k ohm 1/4W 1 AA
R11 VRD-B12EF563J Resistor 56k ohm 1/4W 1 AA
R30 VRD-B12EF153J Resistor 15k ohm 1/4W 1 AA
R31 VRD-B12EF472J Resistor 4.7k ohm 1/4W 1 AA
R40 VRD-B12EF102J Resistor 1.0k ohm 1/4W 1 AA
R41 VRD-B12EF332J Resistor 3.3k ohm 1/4W 1 AA
R50 RR-DZA143DRE0 Resistor array 150k ohm x 4 1 AC
R51-54 VRD-B12EF153J Resistor 15k ohm 1/4W 4 AA
R60 VRD-B12EF105J Resistor 1M ohm 1/4W 1 AA
R70-72 VRD-B12EF472J Resistor 4.7k ohm 1/4W 3 AA
R73-75 VRD-B12EF104J Resistor 100k ohm 1/4W 3 AA
(J27) VRD-B12EF151J Resistor 150 ohm 1/4W 1 AA

R-3A88

29

R-3A88

Note: The parts marked "∆" may cause undue microwave exposure.

The parts marked "*" are used in voltage more than 250V.

REF. NO. PART NO. DESCRIPTION Q'TY CODE

(J35) VRD-B12EF511J Resistor 510 ohm 1/4W 1 AA
RY1 RRLY-A080DRE0 Relay (OJ-SS-124LM) 1 AG
RY2 RRLY-A076DRE0 Relay (OMIF-S-124LM) 1 AK
SP40 RALM-A014DRE0 Buzzer (PKM22EPT-THAI) 1 AG
T1 RTRNPA098DRE0 Transformer 1 AT
VRS1 RH-VZA032DRE0 Varistor (10G471K) 1 AE
ZD2 VHEHZ4C3///-1 Zener diode (HZ4C-3) 1 AA
3- 2 FPNLCB225WRK0 Control panel frame with key unit 1 AZ
3- 2-1 FUNTKA753WRE0 Key unit 1 AV
3- 3 JBTN-A927WRF0 Open button 1 AF
3- 4 MSPRCA050WRE0 Open button spring 1 AB
3- 5 XEPSD30P08XS0 Screw : 3mm x 8mm 2 AA

OVEN PARTS

4- 1 PHOK-A095WRF0 Latch hook 1 AN

∆

4- 2 LBNDKA095WRP0 Capacitor holder 1 AM
4- 3 NFANJA029WRE0 Fan blade 1 AL
4- 4 PDUC-A599WRP0 Fan duct 1 AK

∆

4- 5 FOVN-A333WRT0 Oven cavity 1 BD
4- 6 LANGFA171WRP0 Chassis support 1 AG
4- 7 MLEVPA194WRF0 Switch lever 1 AG
4- 8 NCPL-A045WRF0 Coupling 1 AH
4- 9 PCOVPA275WRE0 Waveguide cover 1 AR
4-10 PCUSGA339WRP0 Cushion 1 AG
4-11 PCUSUA329WRP0 Cushion 1 AC
4-12 PDUC-A597WRF0 Air guide 1 AG
4-13 PFILWA041WRE0 Lamp filter 1 AF
4-14 PPACGA084WRF0 TTM packing 1 AF
4-15 LANGQA368WRP0 Fuse angle 1 AL
4-16 LANGQA343WRP0 Thermal cut-out (Fan) mounting angle 1 AK
4-17 PCUSGA378WRP0 Cushion 1 AL
4-18 PCUSGA388WRP0 Cushion 1 AK
4-19 PCUSUA278WRP0 Cushion 1 AC

DOOR PARTS

5- 1 FDORFA283WRT0 Door panel 1 AY

∆

5- 2 PSHEPA382WRE0 Sealer film 1 AH
5- 3 GCOVHA342WRF0 Choke cover 1 AM
5- 4 GWAKPA354WRF0 Door frame 1 AN

∆

5- 5 HPNL-A657WRR0 Door screen 1 AT
5- 6 LSTPPA139WRF0 Latch head 1 AF

∆

5- 7 MSPRTA084WRE0 Latch spring 1 AB
5- 8 XCPSD40P06000 Screw; 4mm x 6mm 2 AA

MISCELLANEOUS

6- 1 FROLPA057WRK0 Roller stay 1 AQ
6- 2 NTNT-A051WRE0 Turntable tray 1 AR
6- 3 TINS-A568WRR0 Operation manual (English) 1 AQ
6- 4 FW-VZB045WRE0 Switch harness 1 AH
6- 5 FW-VZB494WRE0 Main wire harness 1 AW
6- 6 QW-QZA150WRE0 High voltage wire B 1 AF

*

6- 7 LHLDWA011WRE0 Purse lock “M” 1 AB
6- 8 TCAUHA214WRR0 Caution label 1 AC
6- 9 PSHE-A069WRR0 Menu label 1 AM
6-10 TSPCNC326WRR0 Name plate 1 AE
6-11 PZET-A012WRE0 Terminal insulator 1 AB
6-12 QTANP0020YBE0 Connector 1 AA
6-13 TCADCA565WRR0 Cook book (Thai) 1 AZ
6-14 QW-QZA177WRE0 Earth wire 1 AK
6-15 TLABPA032WRR0 Grounding label 1 AG
6-16 TINS-A567WRR0 Operation manual (Thai) 1 AQ

SCREWS,NUTS AND WASHERS

7- 1 XFPSD40P08K00 Screw : 4mm x 8mm 9 AA
7- 2 XFPSD30P06000 Screw : 3mm x 6mm 2 AA
7- 3 XHTSD40P08RV0 Screw : 4mm x 8mm 3 AA
7- 4 XHTSD40P08000 Screw; 4mm x 8mm 1 AA
7- 5 XOTSD40P12RV0 Screw : 4mm x 12mm 14 AA
7- 6 XOTSD40P12000 Screw : 4mm x 12mm 9 AA
7- 7 XVPSD40P20000 Screw; 4mm x 20mm 1 AA
7- 8 XFPSD30P10000 Screw; 3mm x 10mm 1 AA

30

HOW TO ORDER REPLACEMENT PARTS

To have your order filled prompty and correctly, please furnish the following information.

1. MODEL NUMBER 2. REF. NO.

3. PART NO. 4. DESCRIPTION

R-3A88

PACKING AND ACCESSORIES

DOOR PROTECTION SHEET
SPADPA204WRE0



MENU LABEL
WARRANTY CARD

OPERATION MANUAL (THAI)

VIDEO TAPE

ROLLER STAY

OPERATION MANUAL (ENGLISH)

TRAY HOLDER
SPADFA340WRE0

TURNTABLE TRAY

COOK BOOK

TOP PAD ASSEMBLY
FPADBA311WRK0

PLASTIC BAG
SSAKHA034WRE0

BOTTOM PAD ASSEMBLY
FPADBA312WRK0

INTO THE
OVEN CAVITY

GLASS COOK WARE

TRAY PAD

PACKING CASE
SPAKCC767 WRE0

Not replaceable items.

31

R-3A88

1

OVEN AND CABINET PARTS

6-2

A

6-1

B

4-12

4-11

C

2

1-13

4-13

1-4

3

2-1

1-12

6-8

1-3
6-10

45

7-5

7-5

7-1

7-6

7-6

6

7-5

A

B

7-5

C

D

E

4-5

4-8

4-9

F

2-3

G

2-4

7-5

H

4-18

2-2

7-1

4-14

x2

7-6

1-14

1-15

7-3

4-7

7-5

7-5

7-1

6-15

4-19

D

7-6

6-14

A

7-3

1-17

1-9

E

4-10

1-5

1-1

7-6

1-6

4-15

7-4

7-6

4-6

1-10

7-3

F

6-11

4-1

1-1

1-4

1-2

4-3

7-1

7-1

7-2

4-2

4-4

1-16

4-17

1-9

7-1

1-7

A

4-16

7-7

1-11

7-8

G

1-8

7-2

7-5

H

1

2

7-57-6

2-4

3

32

45

6

R-3A88

1

CONTROL PANEL PARTS

A

B

C

3- 3

2

3- 2

3-2-1

3- 4

3

3- 1

45

3- 5

DOOR PARTS

5-3

5-2

6

A

B

C

D

E

F

G

MISCELLANEOUS

6-4

5-4

5-1

5-5

5-7

5-6

6-5

D

E

F

G

H

1

Actual wire harness may be different from illustration.

6-6

2

3

33

6-7

45

6-12

H

6

R-3A88

34

'96SHARP CORP. (3U0.07E) Printed in Japan