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15

This unit uses CMOS LSI in the integral part of the
circuits. When handling these parts, the following pre-
cautions 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 electric-
ity 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 PW boards con-
taining them in aluminium foil.

2) When soldering, ground the technician as shown in

the figure and use grounded soldering iron and
work table.

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

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

A. On some models, the power supply cord be-

tween 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 con-
trol panel while keeping it connected to the oven.

B. On some models, the power supply cord be-

tween the touch control panel and the oven
proper is so long enough that they may be
separated from each other.

For those models, therefore, it is possible to
check and repair the controls of the touch control
panel while keeping it apart from the oven proper;
in this case you must short both ends of the door
sensing switch (on PWB) of the touch control
panel with a jumper, which brings about an
operational state that is equivalent to the oven

door being closed. As for the sensor-related
controls of the touch control panel, checking
them is possible if the dummy resistor(s) with
resistance equal to that of the controls are used.

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 termi-
nal 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).

Tools required to service the touch control panel as-
sembly.
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

1) Before turning on the power source of the control

unit, remove the aluminium foil applied for prevent-
ing static electricity.

2) Connect the connector of the key unit to the control

unit being sure that the lead wires are not twisted.

3) After aluminium foil is removed, be careful that

abnormal voltage due to static electricity etc. is not
applied to the input or output terminals.

4) Attach connectors, electrolytic capacitors, etc. to

PWB, making sure that all connections are tight.

5) Be sure to use specified components where high

precision is required.

approx. 1M ohm

16

To remove the outer case proceed as follows.
1. Disconnect the oven from power supply.
2. Open the oven door and wedge it open.
3. Remove the eight (8) screws from rear and along the

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 oven.

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 6 form the basis of the 3D checks.

CAUTION: DISCHARGE HIGH VOLTAGE CAPACI-

TOR BEFORE TOUCHING ANY OVEN
COMPONENT OR WIRING.

1. Disconnect oven from power supply.
2. 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.

To prevent an electric shock, take the following
manners.
1. Before wiring,

1) Disconnect the power supply.
2) Open the door and wedge the door open.
3) Discharge the high voltage capacitor and wait for

60 seconds.

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

1) High voltage parts:

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

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)

Fan blade, Fan motor, Switch.

3. Do not catch the wire leads in the outer case cabinet.
4. Insert the positive lock connector certainly until its pin

is locked. And make sure that the wire leads should
not  come off even if the wire leads is pulled.

5. To prevent an error function, connect the wire leads

correctly, referring to the Pictorial Diagram.

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

1. CARRY OUT 3D CHECKS.
2. Disconnect the wire leads (main wire harness and H.V.

fuse) from high voltage transformer.

3. Disconnect the filament lead of high voltage trans-

former from the magnetron.

4. Disconnect the filament lead of the high voltage trans-

former from high voltage capacitor.

5. Remove the two (2) screws holding the transformer to

bottom plate from below.

6. Remove the two (2) screws holding the transformer to

bottom plate from above.

7. Remove the transformer.

17

To remove the components, proceed as follows.
1. CARRY OUT 3D CHECKS.
2. Disconnect the H.V. fuse from the high voltage trans-

former.

3. Disconnect the H.V. wire of the H.V. rectifier assembly

from the magnetron.

4. Remove one (1) screw holding capacitor holder to the

oven cavity back plate.

5. Disconnect the filament lead of the high voltage trans-

former from the H.V. capacitor.

6. Remove one (1) screw holding earth side terminal of high

voltage rectifier assembly, and remove capacitor holder.

7. Disconnect all the leads and terminals of high voltage

rectifier assembly from high voltage capacitor.

8. Disconnect the H.V. fuse from the high voltage capacitor.
9. Now H.V. rectifier assembly, H.V. fuse and H.V. ca-

pacitor should be free.

CAUTION: WHEN REPLACING HIGH VOLTAGE

RECTIFIER ASSEMBLY, ENSURE THAT
THE CATHODE (EARTH) CONNECTION
IS SECURELY FIXED TO THE CAPACI-
TOR HOLDER WITH AN EARTHING
SCREW.

CAUTION: DO NOT REPLACE ONLY HIGH VOLT-

AGE RECTIFIER. WHEN REPLACING IT,
REPLACE HIGH VOLTAGE RECTIFIER
ASSEMBLY.

Removal
1. CARRY OUT 3D CHECKS.
2. Disconnect the wire leads from the magnetron.
3. Carefully remove the three (3) screws holding the

magnetron to the waveguide flange.

4. Lift up magnetron with care so that the magnetron

antenna is not hit by any metal object around antenna.

5. Now, the magnetron is free.
Reinstall
1. Reinstall the magnetron to the waveguide flange with

three (3) screws.

2. Reconnect the wire leads to the magnetron. Refer to

"PICTORIAL DIAGRAM".

3. Reinstall the outer case and check that the oven is

operating properly.

CAUTION: WHEN REPLACING THE MAGNETRON,

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

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

®

 connector.

3. Pull down on the positive lock

®

 connector.

CAUTION: WHEN CONNECTING THE POSITIVE

LOCK

®

 CONNECTORS TO THE TERMI-

NALS, INSTALL THE POSITIVE LOCK

®

 SO

THAT THE LEVER FACES YOU.

Terminal

Push

Pull down

1

2

Lever

Positive lock®

connector

1. Disconnect the oven from the power supply.
2. Remove the turntable and turntable support from the

oven cavity.

3. Turn the oven over.
4. Cut the four (4) bridges holding the turntable motor

cover to the bottom plate with the cutting pliers as
shown in Figure C-2.

CAUTION: DO NOT DROP THE TURNTABLE MOTOR

COVER INTO THE OVEN AFTER CUTTING
THE BRIDGES. BECAUSE IT WILL DAM-
AGE THE WIRE LEADS OF THE MOTOR
AND IT IS DIFFICULT TO REMOVE IT OUT
OF THE OVEN.

5. Remove the turntable motor cover from the bottom

plate.

6. Disconnect the wire leads from the turntable motor.
7. Remove the single (1) screw holding the turntable

motor to the oven cavity.

8. Remove the turntable motor from the oven cavity.
9. Remove the O-ring and washer from the turntable

motor.

10.Now, the turntable motor is free.

1. Remove the any sharp edges on the turntable motor

cover and the bottom plate with the cutting pliers.

2. Reinstall the O-ring.

18

Gap

Rotor

Bracket

Stator

Groove joint pliers

Coil

Shaft

Axis

Stator

Rotor

These are the positions 
that should be pinched 
with pliers.

3. Apply the grease (Shinetsu  silicone grease G-420 of

Sinetsu Chemical Co. Ltd. or Toray Silicone grease
SH-14 of Toray Silicone Co., Ltd.) to the O-ring and the
base of the turntable motor shaft as shown in Figure C-
3.

4. Reinstall the turntable motor with the O-ring and washer

to the oven cavity with the single (1) screw.

5. Reconnect the wire leads to the turntable motor.
6. Insert the tab of the turntable motor cover into the hole

of the bottom plate as shown in Figure C-2.

7. Reinstall the turntable motor cover to the bottom plate

w i t h   o n e   ( 1 )   s c r e w   X H T S D 4 0 P 0 8 R V 0   o r
XFPSD40P08K00 as shown in Figure C-2.

REMOVAL
1. CARRY OUT 3D CHECKS.
2. Disconnect the wire leads from the fan motor.
3. Remove the one (1) screw holding the chassis support

to the oven cavity front plate.

4. Remove the chassis support .
5. Release the filament lead of the power transformer and

the H.V. wire from the fan duct.

6. Remove the one (1) screw holding the light mounting

plate to the oven cavity.

7. Release the wire leads (to the oven lamp) from the hole

of the fan duct.

8. Remove the one (1) screw holding the fan duct to the

waveguide flange.

9. Release the fan motor assembly from the oven cavity.
10.Remove the fan blade from the fan motor shaft accord-

ing to the following procedure.

11.Hold the edge of the rotor of the fan motor by using a

pair of groove joint pliers.

12.Remove the fan blade assembly from the shaft of the

fan motor by pulling and rotating the fan blade with your
hand.

13.Now, the fan blade will be free.

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

the fan duct.

15. Now, the fan motor is free.

Bottom Plate

Bridges

Turnrable
Motor Cover

Tab

Hole

Cutting Pliers

Screw; XHTSD40P08RV0 or
            XFPSD40P08K00

Washer

O-ring

Base of turntable
motor shaft

Turntable motor

O-ring

Washer

Apply the 
grease here

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
to the following procedure.

3.

Hold the centre of the bracket which supports the
shaft of the fan motor on the flat table.

4.

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

5.

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.

6.

Install the fan motor assembly to the oven cavity by
fitting the tabs of the fan duct into the holes of the oven
cavity and the waveguide flange.

7.

Reinstall the light mounting plate to the oven cavity
with the one (1) screw.