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R-254M - 21

1. CARRY OUT 3D CHECKS.
2. Disconnect the wire leads from the fan motor.
3. Remove the two (2) screws holding the fan motor to the

oven cavity back plate.

4. Now, the fan motor is free.
5. Remove the fan blade from the fan motor shaft accord-

ing to the following procedure.
1) Hold the edge of the rotor of the fan motor by using

a pair of groove joint 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.

1.

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

1)

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

2)

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.

2.

Install the fan motor to the oven cavity back plate with

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

material in four corners.

3. Where the corners have been snipped off bent corner

areas flat. No sharp edge must be evident after re-
moval of turntable motor cover.

4. Disconnect the wire leads from the turntable motor and

remove the one (1) screw holding the turntable motor.

5. Turntable motor is now free.
6. After replacement use the one (1) screw to fit the

turntable motor cover.

1. CARRY OUT 3D CHECKS.
2. Disconnect the main wire harness and the stop switch

harness from the control panel.

3. Remove the one (1) screw holding the control panel to

the oven cavity.

4. Lift the control panel assembly and pull it forward.

Now, the control panel assembly is free.

1. CARRY OUT 3D CHECKS.
2. Disconnect the H.V. wire B and filament lead of the

transformer from the magnetron.

3. Remove the chassis support screw and the screw

holding chassis support to magnetron.

4. Move the air intake duct to left.
5. Carefully remove two (2) screws holding magnetron to

the waveguide, when removing the screws hold the
magnetron to prevent it from falling.

6. Remove the magnetron from the waveguide with care

so the magnetron antenna is not hit by any metal object
around the antenna.

CAUTION: WHEN REPLACING THE MAGNETRON,

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

REINSTALL THE MAGNETRON TO WAVE
GUIDE FLANGE WITH THE TWO (2)
SCREWS DIAGONALLY.

1. CARRY OUT 3D CHECKS.
2. Disconnect the filament leads of high voltage trans-

former from high voltage capacitor and the magnetron.

3. Disconnect the seconary wire B from the high voltage

capacitor.

4. Remove the four (4) screws holding the transformer to

base plate.

5. Remove the transformer.
6. Now the high voltage transformer is free.

R-254M - 22

1. CARRY OUT 3D CHECKS.
2. Remove the one (1) screw and nut holding the green/

yellow wire to the oven cavity.

3. Disconnect the leads of the power supply cord from the

noise filter, referring to the Figure C-1(a).

4. Release the power supply cord from the rear cabinet.
5. Now, the power supply cord is free.

1. Insert the moulding cord stopper of power supply cord

into the square hole of the rear cabinet, referring to the
Figure C-1(b). Installation of Power supply cord.

2. Install the earth wire lead of power supply cord to the

oven cavity with one (1) screw and nut, tighten the
screw.

3. Connect the brown and blue wire leads of power supply

cord to the noise filter correctly, referring to the Pictorial
Diagram.

OVEN CAVITY
BACK PLATE

SQUARE HOLE

MOULDING
CORD
STOPPER

POWER SUPPLY
CORD

GROMMET
MOULDING

1. CARRY OUT 3D CHECKS.
2. Disconnect the wire lead from the oven lamp, refer-

ring to "Positive lock

®

 connector removal".

3. Lift up the oven lamp with release.
4. Now, the oven lamp is free.

BULB

LOCK

the two (2) screws.

3. Reconnect the wire leads to the fan motor, referring to

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

®

 connector.

3. Pull down on the positive lock

®

 connector.

CAUTION: WHEN YOU (SERVICE ENGINEERS) CON-

NECT THE POSITIVE LOCK

®

 CONNEC-

TORS TO THE TERMINALS, CONNECT
THE POSITIVE LOCK

®

 SO THAT THE LE-

VER FACES YOU .

Terminal

Push

Pull down

1

2

Lever

Positive lock®

connector

the pictorial diagram.

Coil

Gap

Rotor

Bracket

Stator

Groove joint pliers

Shaft

Axis

Stator

Rotor

These are the position 
where should be 
pinched with pliers

Shaft

Table

Center of 
bracket

OVEN CAVITY
BACK PLATE

BROWN WIRE

POWER 
SUPPLY CORD

CHASSIS SUPPORT

BLUE WIRE

NOISE FILTER

N

L

F1

RED

WHT

R-254M - 23

1. CARRY OUT 3D CHECKS.
2. Disconnect the wire leads from the switches and con-

trol panel.

3. Remove the control panel assembly from the oven

cavity front flange. Referring to chapter "CONTROL
PANEL ASSEMBLY REMOVAL".

4. Remove the two (2) screw holding the latch hook to the

oven flange.

5. Remove the latch hook assembly from the oven flange.
6. To remove the switch.
6-1. With pushing outward on the tab that is holding the

switch, turn the switch so that the post is an axis.

6-2. Pull out the switch from the latch hook. Do not break

the post or tab of the latch hook.

6-3. Now the switch is free.

Re-install
1. Re-install each switch in its place. The monitored latch

switch is in the lower position and the monitor switch is
in the middle position. The stop switch is in the upper
position.

2. Re-connect wire leads to each switch. Refer to chapter

“Pictorial Diagram”.

3. Secure latch hook (with two (2) mounting screws) to

oven flange.

4. Re-install the control panel assembly to the oven cavity

front flange.

5. Re-connect wire leads to the control unit. Refer to

chapter “Pictorial Diagram”.

6. Make sure that monitor switch is operating properly and

check continuity of the monitor circuit. Refer to chapter

1. CARRY OUT 3D CHECKS.
If the monitored latch switch, stop switch and monitor
switch do not operate properly due to a misadjustment,
the following adjustment should be made.
2. Loosen the two (2) screws holding the latch hook to the

flange of the oven front face.

3. With the 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 should be less than 0.5mm. The horizontal
position of the latch hook should be adjusted so that
the monitor switch is activated with the door closed.
The vertical position of the latch hook should be
adjusted so that the stop switch and the monitored
latch switch are activated with the door closed.

4. Secure the screws firmly.
5. Check the operation of all switches. If each switch has

not activated with the door closed, loosen screw and
adjust the latch hook position.

After adjustment, make sure of the following.
1. In and out play of the 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 door
toward the oven face. Both results (play in the door)
should be less than 0.5mm.

2. The monitored latch switch and stop switch interrupt

the circuit before the door can be opened.

3. The monitor switch contacts (COM-NC) close when the

door is opened.

4. Re-install outer case and check for microwave leakage

around the door with an approved microwave survey
meter. (Refer to Microwave Measurement Procedure.)

“Test Procedure”, and Adjustment Procedure below.

Latch hook

Tab

SW3: Stop switch 

SW2: Monitor switch 

SW1:  Monitored latch switch 

Tab

Tab

Latch hook

SW3: Stop switch

Door

SW2: Monitor switch

SW1:Monitored latch switch

Latch heads

R-254M - 24

10

5

4

12

8

7

9

11

3

2

1

Choke Cover

Door Frame

Putty Knife

6

REMOVAL
1. Disconnect the power supply cord.
2. Open the door slightly.
3. Remove the choke cover taking care not to break

clips by inserting an  iron plate (thickness of about
0.5mm) or flat type screw driver to the gap between
the choke cover and door panel as shown Figure C-
4 to free the engaged parts.

4. Release choke cover  from door panel.
5. Now choke cover is free.

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

of upper and lower oven hinges by lifting up.

7. 1. Remove door assy by removing screws (4).
8. Release door panel from tabs of door frame and

remove door frame by sliding the door panel down-
ward.

9. Now, door panel with inner sealer film is free.
10.Tear inner sealer film from door panel.
11.Now, door panel is free.
12.Slide latch head upward and remove it from door

frame with releasing latch spring from door frame and
latch head.

13.Now, latch head and latch spring are free.
14.Remove Glass Stopper Screw (noting position of

15.Slide glass towards Glass Stopper position and

16. Lift upper edge of glass, which will now be free

17.Refitting is a reversal of the above when refitting,

RE-INSTALL
1. Re-install the outer door glass to the door frame with

the glass stopper.

2. Hold the glass stopper with the one (1) screw.
3. Re-install latch spring to the head. Re-install latch

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

4. Re-install door panel to door frame by fitting tabs of

door frame to holes of door panel.

5. Put sealer film on door panel. Refer to “Inner Sealer

Film” and figure C-6, on how to handle the new film.

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.
Note: After any service to the door;
(A) Make sure that monitored latch switch, stop

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 Micro-
wave 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
air-tight, moisture (condensation)-tight or light-
tight. Therefore, occasional appearance of mois-
ture, light or sensing of gentle warm air move-
ment around oven door is not abnormal and do
not of themselves, indicate a leakage of micro-
wave energy from oven cavity.

INNER SEALER FILM

Installation
1. Tear away the backing film.
3. Put the pasted side of the inner sealer film on the door

panel.

Door film

Finger tab

Backing film

PIN

PIN

LOWER
OVEN HINGE

UPPER
OVEN HINGE

LOWER
OVEN HINGE

CHOKE COVER

DOOR
PANEL

DOOR SUB 
ASSEMBLY

SLIT CHOKE