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

blade screwdriver.

3) Lift up and push the door.

NOTE:
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

assembly, 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) Disconnect the leadwire from lamp and MGT

thermostat.

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).

magnetron. To prevent microwave leakage,
tighten the mounting screws properly, making sure
there is no gap between the waveguide and the
magnetron.

5-4

Magnetron

Air Duct

5-5

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.

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

with a slotted screwdriver.

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 the turntable motor

VERY CAREFULLY.

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

removing.

Wire Leads

Turntable Motor

H.V.
Capacitor

H.V.
Transformer

Suction
Guide

Fan Motor ASS'Y

1) Remove the two screws securing the cover

assembly to the oven cavity.

2) Disconnect the leadwire from the circulation motor

terminal and the sheath heater.

3) Remove the screws of the thermistor, guide assy-

chamber and lift up the guide assy-chamber.

4) Remove a hex nut securing the circulation fan to

shaft of the C-motor.

5) Remove screws securing the motor bracket to the

guide assy-chamber.

6) Remove two hex nuts securing the C-motor to the

motor bracket.

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) Take off the PCB SUB ASS’Y from the control

panel.

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 SWITCHES 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 that

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

• Tighten the mounting screw.

5-6

Latch Board

Secondary Interlock Switch

Interlock Monitor Switch

Primary Interlock Switch

When the door release button is depressed slowly
with the door closed, an audible click should be
heard at the same time or successively at
intervals. When the button is released slowly, the
latches should activate the switches with an
audible click.
If the latches do not activate the switches when
the door is closed, the switches should be a
adjusted in accordance with the adjustment
procedure. Disconnect the wire lead from the
primary switch. Connect the ohmmeter leads to
the common (COM) and normally open (NO)
terminal of the switch. The meter should indicate
an open  circuit in the door open condition.
When the door is closed, the meter should
indicate a closed circuit.
When the primary switch operation is abnormal,
make the necessary adjustment or replace the
switch only with the same type of switch.

Disconnect the wire lead from the secondary
switch.
Connect the ohmmeter leads to the common
(COM) and normally open (NO) terminals of the
switch. The meter should indicate a open circuit in
the door open condition. When the door is closed,
meter should indicate an closed circuit. When the
secondary switch operation is abnormal, make
the necessary adjustment or replace the switch
only with the same type of switch.

Disconnect the wire lead from the monitor switch.
Connect the ohmmeter leads to the common
(COM) and normally closed (NC) terminals of the
switch. The meter should indicate closed circuit in
the door open condition. When the door is closed,
meter should indicate an open circuit. When the
monitor switch operation is abnormal, replace with
the same type of switch.
NOTE: After repairing the door or the interlock
system, it is necessary to do this continuity
test before operating the oven.

5-7

TYPE NO. SZM-V 16-FA-63 OR VP-533A-OF FOR PRIMARY SWITCH 
TYPE NO. SZM-V 16-FA-61 OR VP-531A-OF FOR MONITOR SWITCH 
TYPE NO. SZM-V 16-FA-63 OR VP-533A-OF FOR SECONDARY SWITCH

SWITCHES

Check for continuity of the switch

(Wire leads removed)

with a Multi-meter

Primary
Switch

Monitor
Switch

Secondary
Switch

NOTE: After checking for the continuity of switches, make sure that are

correctly connected.

Door

open

Door

close

COM

NO

COM

NC

COM  

NO