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R-774M - 25

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 H.V. wire A from the high voltage

transformer.

4. Disconnect the main wire harness from the high volt-

age transformer.

5. Remove the two (2) screws and one (1) washer holding

the transformer to the base plate.

7. Remove the transformer.
8. Now the high voltage transformer 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 one (1) screw holding the chassis support

to the magnetron.

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

the control panel frame.

7. Remove the control unit assembly (CPU unit and

Power unit) from the control panel frame.

8. Remove the six (6) screws holding the key / jog unit to

the control panel frame.

9. Remove the key / jog unit from the control panel frame.
10.Remove the vari knob and the rotary knob from the key

/ jog unit.

11.Now, the key / jog unit is free.

1. CARRY OUT 3D CHECKS.
2. Disconnect the wire leads and the connectors from the

control unit.

3. Lift up the control panel assembly and pull it forward.

Now the control panel assembly is free.

Key / Jog unit
4. Disconnect the connector CN-G from the CPU unit.
5. Remove the two (2) screws holding the LCD holder to

the control panel frame.

6. Remove the four (4) screws holding the power unit to

11.Remove the fan duct 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 assembly from the shaft of

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

3) Now, the fan blade is free.

1. CARRY OUT 3D CHECKS.
2. Remove the one (1) screw holding the noise filter to the

chassis support.

3. Release the noise filter from the tabs of the fan duct.
4. Remove the one (1) screw holding the chassis support

to the oven cavity front flange.

5. Remove the chassis support from the oven cavity.
6. Disconnect the wire leads from the fan duct.
7. Remove the one (1) screw holding the capacitor holder

to the oven cavity back plate.

8. Release the tabs of the capacitor holder from the fan

duct.

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

oven cavity back plate.

10.Remove the fan duct from the oven.

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

the high voltage rectifier assembly.

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

cavity rear plate.

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

oven cavity rear plate.

7. Release the capacitor holder from the fan duct.
8. Remove the high voltage capacitor from the capacitor

holder.

9. Disconnect the high voltage wire B and the high voltage

rectifier assembly from the high voltage capacitor.

10.Disconnect the high voltage rectifier assembly from the

high voltage wire B.

11.Now, the high voltage rectifier assembly and the high

voltage capacitor 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.

R-774M - 26

12.Remove the two (2) screws and nuts holding the fan

motor to the fan duct.

13.Now, the fan motor is free.

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

screws and nuts.

2. 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) 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.

3. Insert the tabs of the capacitor holder to the fan duct.
4. Install the fan duct to the oven cavity back plate with the

one (1) screw.

5. Install the capacitor holder to the oven cavity back plate

with the one (1) screw.

6. Re-install the chassis support to the oven cavity with the

one (1) screw.

7. Install the noise filter to the fan duct and the chassis

support with the one (1) screw.

8. Re-connect the wire leads to the fan motor.

Shaft

Table

Center of 
bracket

Coil

Gap

Rotor

Bracket

Stator

Groove joint pliers

Shaft

Axis

Stator

Rotor

These are the position 
wthat should be pinched 
with groove-joint pliers

Removal
1. Disconnect the oven from the power supply.
2. Remove the turntable from the oven cavity.
3. Turn the oven over.
4. Cut the four (4) bridges holding the turntable motor

cover to the base plate with cutting pliers as shown in
Figure C-1(a).

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

to the turntable motor angle.

8. Remove the turntable motor from the turntable motor

angle. Now, the turntable motor is free.

Re-install
1. Remove the any sharp edges on the turntable motor

cover and the base plate with the cutting pliers.

2. Re-install turntable motor by locating shaft onto turnta-

ble motoor shaft to the turntable motoor angle with the
one (1) screw.

3. Re-connect the wire leads to the turntable motor.
4. Insert the two (2) tabs of the turntable motor cover into

the slits of the base plate as shown in Figure C-1(b).

5. Re-install the turntable motor cover to the base plate

with the screw (XHTSD40P08RV0) as shown in Figure
C-1(b).

Cutting pliers

Bridges

Bridges

Turntable motor 
cover

Screw; 
XHTSD40P08RV0 

Turntable motor cover

Base plate  

Tabs 

Slits 

R-774M - 27

1. CARRY OUT 3D CHECKS.
2. Remove the wire leads as Positive lock

®

 connector

removal above.

3. Lift up the oven lamp from its retaining clips.
4. Now, the oven lamp is free.

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

wire to the cavity back plate.

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

noise filter, referring to the Figure C-4(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 power angle, referring to the
Figure C-4(b).

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

oven cavity with one (1) screw and tight the screw.

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

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

1. CARRY OUT 3D CHECKS.
2. Remove the two (2) screws holding the two (2) termi-

nals of the main wire harness to the top heating
element.

3. Remove the two (2) screws holding the two (2) grill

heater angles to the top of the oven cavity.

4. Remove the two (2) grill heater angles from the oven

cavity.

5. Remove the top heating element from the top of the

oven cavity.

6. Now the top heating element is free.

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 ENGNEERS) CON-

NECT THE POSITIVE LOCK

®

 CONNEC-

TORS TO THE TERMINALS, CONNECT
THE POSITIVE LOCK

®

 SO THAT THE LE-

VER FACES YOU (SERVICE ENGNEERS).

BULB

LOCK

Terminal

Push

Pull down

1

2

Lever

Positive lock®

connector

1. CARRY OUT 3D CHECKS.
2. Remove the turntable motor cover from the base plate,

referring to "TURNTABLE MOTOR REPLACEMENT".

3. Disconnect the wire leads from the bottom heating

element.

POWER
SUPPLY CORD

MOULDING
CORD STOPPER

OVEN CAVITY
BACK PLATE

SQUARE HOLE

Power supply cord

Green/ Yellow
wire

Brown wire

Oven cavity back plate 

Blue wire

Noise filter

Screw

L

TP

F 8 A

TL

RED

15 A

WHT

N

R-774M - 28

4. Remove the two (2) nuts holding the bottom heating

element to the oven cavity.

5. Remove the heater cover and the heater packing from

the bottom heating element.

6. Remove the bottom heating element from the oven

cavity .

1. CARRY OUT 3D CHECKS.
2. Remove the control panel assembly referring to "CON-

TROL PANEL ASSEMBLY REMOVAL".

3. Remove the open lever from the oven cavity front plate

by removing the control panel assembly.

4. Disconnect the leads from all switches.
5. Remove the two (2) screws holding the latch hook to

the oven cavity.

6. Remove the latch hook.
7. Remove the switch(es) from the latch hook by pushing

the retaining tab backwards slightly and turning the
switch(es) on the post.

8. Now the switch(es) is free.

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

the oven cavity front flange.

3. With the door closed, adjust the latch hook by moving

it back and forward or up and down. In and out play of
the door allowed by the latch hook should be less than
0.5 mm. The horizontal position of the latch hook
should be placed where the monitor switch has acti-
vated with the door closed. The vertical position of the
latch hook should be placed where the monitored latch
switch and stop switch have activated with the door
closed.

4. Secure the screws with washers firmly.
5. Make sure of the all switches operation. If the latch

head has not pushed the plungers of the monitor
switch with door closed, adjust the latch hook position.
At that time, the latch head should have pushed the
plungers of the monitored latch switch and stop switch.
If the latch head has not pushed the plungers of the
monitored latch switch and stop switch with door
closed, loose two (2) screws holding latch hook to
oven cavity front flange and adjust the latch hook
position.

1. In and out play of door remains less than 0.5 mm when

latched position. First check latch hook position, push-
ing and pulling upper position of the door toward the

oven face. Then check the lower latch hook position,
pushing and pulling lower position of the door toward
the oven face. Both results (play of the door) should be
less than 0.5mm.

2. The stop switch  interrupt the circuit before the door

can be opened.

3. When the door is opened the contacts (COM-NC) of

the monitor switch and monitored latch switch close.
And the contacts (COM-NO) of their switches open.

4. When the door is closed the contacts (COM-NC) of the

monitor switch and monitored latch switch open. And
the contacts (COM-NO) of their switches close.

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

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

1. Disconnect the oven from the 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 door frame as shown
in Figure C-7 to free engaging parts.

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

MONITOR SWITCH

STOP SWITCH

MONITORED
LATCH SWITCH

Tab

Post

Post

Post

Tab

Tab

DOOR

LATCH HOOK

MONITOR SWITCH

MONITORED
LATCH SWITCH

 STOP SWITCH

OPEN LEVER

LATCH
HEADS