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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.

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) 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.

Door seal plate

Remove choke cover cap

Remove door

H.V.
Transformer

Suction
Guide

Fan Motor ASS’Y

H.V.
Diode

H.V.
Capacitor

5-4

5-5

1) Disconnect the leadwire from lamp.

2) Remove the mounting screw to Latch Board.

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.

1) Remove the turntable.
2) Remove the Rotating Ring.
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.

Waveguide

Magnetron

Magnetron
Gasket

Magnetron

Dome

Waveguide 
Bracket

Wire Leads

Turntable Motor

1) Remove the control panel assembly from the

cavity. 

2) Remove screws which hold the timer motor to the

control panel.

3) Remove the timer motor from the control panel.
4) Remove the power control knob and the timer

knob.

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.
• Check for play in the door by pushing the door

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 switches operate properly by
following the continuity test procedure.

5-6

Control Panel

Timer Motor

Power Control 

Knob

Timer Knob

PRIMARY

SWITCH

SECONDARY

SWITCH

ADJUSTMENT 

DIRECTION

MONITOR

SWITCH

MAGNETRON

H.V. TRANSFORMER

PRIMARY

CIRCUIT PROTECTOR

H.V. CAPACITOR

H.V.
DIODE

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-62 OR VP-532A-OF FOR MONITOR SWITCH 
TYPE NO. SZM-V 16-FA-63 OR VP-533A-OF FOR SECONDARY SWITCH

SWITCHES

Check for continuity of the 

Door

Door

(Wire leads removed)

switch with an Ohm-meter

open

closed

Primary
Switch

Monitor
Switch

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

connected correctly.

NO

COM

NC

COM

NO

COM

Secondary
Switch