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23

The "Main PWB" of this model employs lead-free solder. This is indicated by the "LF" symbol printed on the PWB
and in the service manual. The suffix letter indicates the alloy type of the solder.
Example:

Indicates lead-free solder of tin, silver and copper.

When repairing a PWB with the "LF" symbol, only lead-free solder should be used. (Using normal tin/lead alloy solder
may result in cold soldered joints and damage to printed patterns.)
As the melting point of lead-free solder is approximately 40˚C higher than tin/lead alloy solder, it is recommend that
a dedicated bit is used, and that the iron temperature is adjusted accordingly.

As the melting point of lead-free solder (Sn-Ag-Cu) is higher and has poorer wettability, (flow), to prevent damage
to the land of the PWB, extreme care should be taken not to leave the bit in contact with the PWB for an extended
period of time. Remove the bit as soon as a good flow is achieved. The high content of tin in lead free solder will cause
premature corrosion of the bit. To reduce wear on the bit, reduce the temperature or turn off the iron when it is not
required.
Leaving different types of solder on the bit will cause contamination of the different alloys, which will alter their
characteristics, making good soldering more difficult. It will be necessary to clean and replace bits more often when
using  lead-free solder. To reduce bit wear, care should be taken to clean the bit thoroughly after each use.

2) How to clear all counter(user and service) and total

cooking time and used time of filter.

PAD ORDER

DISPLAY

PHONE

(Door close)

•

SET

•

SET

"NUMBER" •

DOUBLE

"NUMBER" • DOUBLE

QUANTITY

CHECK

"NUMBER" • DOUBLE

SIGNAL

"NUMBER" • DOUBLE

SET

•

Sn-Ag-Cu

24

1. Disconnect the 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 grip the door
handle and the door lever assembly 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 dam-

age (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 conditions
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 generating

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.

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

To remove the components, procedure as follows.
1. Disconnect oven from power supply.
2. Open the oven door and wedge it open.
3. Remove the screws from the rear and along side the

edge of the outer case.

4. Slide the case back about 1 inch (3 cm) to free it from

the oven cavity.

5. Lift entire case from the unit.
6. DISCHARGE TWO HIGH VOLTAGE CAPACITORS

7. Now, outer case is free.

N.B.; Step 1,2 and 9 form the basis of the 3D checks.

CAUTION:DISCHARGE TWO HIGH VOLTAGE CA-

PACITORS BEFORE TOUCHING ANY
OVEN COMPONENTS OR WIRING.

To remove rear cabinet and power supply cord:
8. Disconnect the power supply cord from the noise filter.
9. Remove the one (1) screws holding the grounding wire

of power supply cord to the oven cavity.

10.Remove the screws holding the rear cabinet to the

oven cavity and blower motor.

11.Remove the  rear cabinet with the power supply cord

from the oven cavity.

12.Loosen the tab of the cord bushing, and remove the

power supply cord with the cord bushing from the rear
cabinet.

13.Remove the cord bushing from the power supply cord,
14.Now, the power supply cord and rear cabinet are free.

To prevent an 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 two high voltage capacitors and

wait for 60 seconds.

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

1) High voltage parts:

Magnetron, High voltage transformer, High volt-
age capacitor, High voltage rectifier assembly and
High voltage fuse.

2) Hot parts:

Oven lamp, Magnetron, High voltage transformer,

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)

Blower fan blade, Blower fan motor, Switches,
Switch levers, Antenna motors and Sirrer anten-
nas.

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 Pictorial Diagram.

1. CARRY OUT 3D CHECKS.
2. Remove the rear cabinet, too.
3. Disconnect wire lead(s) of high voltage transformer(s)

from magnetron(s).

4. Remove the wire lead(s) of high voltage transformer(s)

from the wire holder.

25

5. Pull out the wire lead(s) of high voltage transformer(s)

from the tube.

6. Disconnect wire lead(s) of high voltage transformer(s)

from high voltage capacitor(s).

7. Disconnect the high voltage fuse(s) from high voltage

transformer(s).

Removal
1. CARRY OUT 3D CHECKS.
2. Remove the rear cabinet, too.
3. Remove the magnetron from the waveguide flange,

referring to "MAGNETRON(S)  REMOVAL".

4. Now, the magnetron with the magnetron thermistor

should be free.

5. Remove the thermistor angle from the magnetron by

pulling out.

6. Straighten the tab of the magnetron thermistor angle

holding the magnetron thermistor.

7. Remove the magnetron thermistor from the thermistor

angle.

8. Now, the magnetron thermistor is free.

Re-install
1. Install the magnetron thermistor to the thermistor angle

as shown in Figure C-1.

2. Hold the magnetron thermistor to the thermistor angle

by bending the tab of the thermistor angle.

3. Insert the thermistor angle between the 2nd. fin and

3rd. fin from the upper fin of the magnetron and push
it until the thermistor angle stops.

NOTE: The magnetron thermistor should be between the

upper fin and the 2nd. fin.

8. Disconnect the main wire harness from high voltage

transformer(s).

9. Remove two (2) screws holding each power trans-

former to base plate.

10.Remove the high voltage transformer(s) from base

plate.

12.Now, high voltage transformer(s) are free.

Removal
1. CARRY OUT 3D CHECKS.
2. Remove the rear cabinet, too.
3. Remove the two (2) screws holding magnetron ex-

haust duct to upper and lower waveguide.

4. Remove the magnetron exhaust duct from oven cavity.
5. Disconnect wire leads from magnetron(s ).
6. Disconnect  magnetron thermistor from the connector

of the stop switch harness.

7. Remove the one (1) screw holding the thermistor angle

to the upper magnetron.

8. Remove the four (4) screws holding each magnetron to

upper and/or lower waveguide. When removing the
screws, hold the magnetron   to prevent it from falling.

9. Remove the magnetron(s) from upper and/or lower

waveguide with care so magnetron  antenna is not hit
by any metal object around antenna.

10.Pull out the thermistor angle from the upper magnet-

ron.

11.Now, the magnetron(s) is (are) free.

CAUTION: WHEN REPLACING MAGNETRON, BE

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

4. Re-install the magnetron to the waveguide flange with

four (4) screws.

5. Re-install the thermistor angle to the waveguide flange

with one (1) screw.

6. Re-install the magnetron exhaust duct to the upper and

lower waveguide flanges with two (2) screws.

7. Route the thermistor harness under the magnetron

temperature fuse.

8. Connect the thermistor harness to the stop switch

harness.

9. Connect the wire leads to the upper magnetron, refer-

ring to the pictorial diagram.

10.Re-install the power supply cord, rear cabinet and

outer case cabinet to the oven by reversing the proce-
dures of  "OUTER CASE, REAR CABINET AND
POWER SUPPLY CORD REMOVAL".

1. CARRY OUT 3D CHECKS.
2. Remove the rear cabinet, too.
3. Remove  two (2) screws holding earth side terminals of

high voltage rectifier assembly to the capacitor holder
and oven cavity.

4. Disconnect all wire leads from the high voltage capacitor.
5. Disconnect high voltage fuse(s) from the high voltage

transformer(s). Now, high voltage fuse(s) is(are) free.

6. Remove the three (3) screws holding the blower motor to

the top of oven cavity, the chassis support and air duct.

7. Disconnect high voltage wire lead(s) of the high volt-

age rectifier assembly from the magnetron(s).
Now, the the high voltage rectifier assembly is free.

8. Remove  two (2) screws holding the capacitor holder to

oven cavity.
Now, the capacitors are free.

Upper magnetron

Upper fin

Tab

Thermistor
angle

Magnetron 
thermistor

26

CAUTION:
1. DISCHARGE THE TWO HIGH VOLTAGE CAPACI-

TORS BEFORE TOUCHING ANY OVEN COMPO-
NENTS OR WIRING.

2. DO NOT REPLACE ONLY THE HIGH VOLTAGE

RECTIFIER. IF IT IS DEFECTIVE, REPLACE THE

HIGH VOLTAGE RECTIFIER ASSEMBLY.

3. WHEN REPLACING THE HIGH VOLTAGE RECTI-

FIER ASSEMBLY AND THE HIGH VOLTAGE CA-
PACITOR, THE CATHODE (EARTH) SIDE TERMI-
NAL OF THE HIGH VOLTAGE RECTIFIER MUST BE
SECURED FIRMLY WITH A EARTHING SCREW.

1. CARRY OUT 3D CHECKS.
2. Remove the rear cabinet, too.
3. Disconnect the wire leads from the blower motor and

noise filter.

4. Remove the one (1) screw holding the blower motor

angle to the oven cavity.

5. Remove the one (1) screw holding the blower motor

angle to the chassis support.

6. Remove the one (1) screw holding the air duct to the

blower motor.

7. Remove the four (4) screws holding the blower motor

angle to the blower motor.

8. Now, the blower motor is free.

UPPER
1. CARRY OUT 3D CHECKS.
2. Disconnect the wire leads from the stirrer motor (up-

per).

3. Remove the one (1) screw holding the stirrer motor

(upper) to the oven cavity.

4. Turn and lift up the stirrer motor (upper).
5. Now, the stirrer motor (upper) is free.

LOWER
1. Disconnect oven from the power supply.
2. Remove the stirrer motor cover by snipping off the

Procedure
1. CARRY OUT 3D CHECKS.
2. Pushing the lever of positive lock

®

 connector, pull down

the connector from the terminal.

3. Now, the connector is free.

CAUTION: WHEN CONNECTING THE POSITIVE

LOCK

®

  CONNECTORS TO THE TERMI-

NALS, CONNECT THE POSITIVE LOCK

®

CONNECTOR SO THAT THE LEVER
FACES YOU.

material in four portions.

3. Where the portions have been snipped off bend the

portions flat. No sharp edge must be evident after
removal of the stirrer motor cover.

4. Disconnect the wire leads from the stirrer motor (lower).
5. Remove the one (1) screw holding the stirrer motor

(Lower) to the oven cavity.

6. Now, the stirrer motor (lower) is free.
7. After replacement use one (1) screw (XOTWW40P08000)

to fit the stirrer motor cover.

Terminal

Push

Pull down

1

Lever

Positive lock®

connector

2

1. CARRY OUT 3D CHECKS.
2. Remove the oven lamp.
3. 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.

4. Lift up the oven lamp socket .
5. Now, the oven lamp socket is free.

Oven lamp
socket

Terminal

Wire lead

Terminal hole

Flat type small
screw driver

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.