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1) Open the door.
2) Remove the choke cover cap very carefully with a

flat-blade screwdriver.

3) Lift up and push the door.

1. After replacing the door, be sure to check that the 

primary switch, monitor switch, and secondary switch
operate normally.

2. After replacing the door, check for microwave energy

leakage with a survey meter. Microwave energy must
be below the limit of 5 mW/cm.(with a 275 ml water
load)

3. When mounting the door assembly to the oven 

asembly, be sure to adjust the door assembly parallel
to the chassis. Also adjust so the door has no play
between the inner door surface and oven frame
assembly. If the door assembly is not mounted 
properly, microwaves may leak from the clearance
between the door and the oven.

1) Discharge the high voltage capacitor.
2) Disconnect the leadwire from magnetron, high 

voltage transformer, and capacitor.

3) Remove the screw holding the high voltage 

transformer to the baseplate.

1) Discharge the high voltage capacitor.
2) Disconnect the leadwire from fan motor, noise filter

and high voltage capacitor.

3) Remove the two screws holding the the suction guide

ASS'Y to the oven cavity and remove the high 
voltage diode earth screw.

4) Remove the screw of the capacitor bracket.
5) Remove the two screws holding the fan motor ASS'Y

to the suction guide ASS'Y

1) Discharge the high voltage capacitor.
2) Disconnect the leadwire from  fan motor, noise filter

and high voltage capacitor.

3) Remove the screw holding the suction guide ASS'Y

to the oven cavity and remove the high voltage diode
earth screw.

4) Remove the screw holding the high voltage capacitor

bracket.

5-4

Remove choke cover cap

Fan Motor ASSY

H. V.
Transformer

H . V .
Diode

Suction
Guide

H. V.
Capacito

Door seal plate

Remove door

1) Disconnect the leadwire from lamp and MGT ther

mostat.

2) Remove the mounting screw to the magnetron.

1) Disconnect the leadwire from the high voltage 

transformer and high voltage capacitor.

2) Carefully remove the mounting screws holding the

magnetron and the waveguide.

3) Remove the magnetron ASS'Y until the tube is clear

from the waveguide.

NOTE:
1. When removing the magnetron, make sure its dome

does not hit any adjacent parts, or it may be 
damaged.

2. When replacing the magnetron, be sure to install the

magnetron gasket in the correct position and be sure
that the gasket is in good condition.

3. After replacing the magnetron, check for microwave

leakage with a survey meter around the magnetron.
Microwave energy must be below the limit of 5
mW/cm

2

.(With a 275 ml. water load).

Make sure that gasket is rigidly attached to the
magnetron. To prevent microwave leakage, tighten
the mounting screws properly, making sure there is
no gap between the waveguide and the magnetron.

1) Remove the turntable.
2) Remove the turntable shaft VERY CAREFULLY with

a slotted hand.

3) Lay the unit down on its back.
4) Remove the turntable motor cover. The turntable

base cover is easily removed by pinching the six
parts with a wire cutting.

5) Disconnect the leadwire from the turntable motor 

terminals.

6) Remove the screw securing the turntable motor to

the oven cavity ASS'Y

7) After repairing the motor, rotate the removed

turntable motor cover.

8) Fit the turntable motor cover's projecting part to the

base plate slit.

NOTE:
1. Remove the wire lead from tne turntable motor VERY

CAREFULLY.

2. Be sure to grasp the connector, not the wires, when

removing.

5-5

Waveguide

Magnetron
Gasket

Magnetron

Dome

Waveguide
Bracket

Lamp

MGT
Themostst

Magnetron

Air Duct

Wire Leads

Turntable Motor

(MS-285SD)

1. Remove the Screw of the back and on the Cavity.

2. Remove the Screw of the Holder.

3. Remove the Holder.

4. Remove the Screw of Sensor Case.

5. Remove the Sensor PCB Ass’y

6. Remove the Reflector.

5-6

Pin

Connector

Holder

Sensor Connector

(CN4)

Sensor Connector

HOOK

Sensor Case

Reflector

Holder

Sensor PCB Ass'y

1) Remove the control panel assembly from the 

cavity.(Refer to control panel assembly removal on
previous page.)

2) Remove screws which hold the PCB SUB ASS'Y to

the control panel.

3) Disconnect the flat cable from the PCB SUB ASS'Y

and take off the PCB SUB ASS'Y.

1) INTERLOCK MECHANISM

The door lock mechanism is a device which has been
specially designed to eliminate completely microwave
activity when the door is opened during cooking and
thus to prevent the danger resulting from the
microwave leakage.

2) MOUNTING OF THE PRIMARY/MONITOR/ 

SECONDARY SWITCHS TO THE LATCH BOARD

3) INSTALLATION AND ADJUSTMENT OF THE LATCH

BOARD TO THE OVEN ASSEMBLY

●

Mount the latch board to the oven assembly.

●

Adjust the latch board in the arrow direction so the

oven door will not have any play in it when the door 
is closed.

●

Tighten the mounting screw.

●

Check for play in the door by pushing the door
release button. Door movement should be less
than 0.5mm. (1/64 inch)
Don't push the door release button while making
adjustment. Make sure that the latch moves 
smoothly after adjustment are completed and that
the screws are tight. Make sure the primary, monitor,
and secondary switch operate properly by following
the continuity test procedure.

5-7

PCB SUB ASSY

Control Panel

Control Panel Deco 

Knob

Tact switch PCB

Dial

Holder LED

ADJUSTMENT
DIRECTION

MONITOR
SWITCH

PRIMARY
SWITCH

SECONDARY
SWITCH

H. V
DIODE

H. V. CAPACITOR

CIRCUIT PROTECTOR

H. V. TRANSFORVER

MAGNETRON

PRIMARY