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1) Disconnect the leadwire from the PCB SUB ASM.

2) Remove the screws for the earth and securing  the

control panel.

3) Lift control panel assembly from the oven by the tab

unhooked.

4) Remove three screws securing the PCB SUB ASM

from the control panel.

5) Separate the key membrane from the control panel.

6) Remove the digitron window and push button.

NOTE : Remove the leadwire and connector VERY

CAREFULLY. Be sure to grasp the connector
and not the wires.

1) Disconnect the leadwire from high voltage

transformer and high voltage capacitor.

2) Carefully remove the mounting screws holding the

magnetron and the waveguide.

3) Remove the magnetron assembly until the tube is

clear from the waveguide.

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

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

14

DIGITRON

WINDOW

PUSH BUTTON

CONTROL PANEL

RELEASE

BUTTON

KEY MEMBRANE

PCB ASSEMBLY

Wave Guide

Magnetron

Noise Filter Ass'y

Fan Motor

Guide Suction

H.V Capacitor

H.V.C Bracket

H.V Diode

Air Duct

Oven Lamp

C. Protector
Ass'y

1 ) Disconnect lead wires from the noise filter ass'y and

remove screw securing the noise filter earth wire to
the back plate.

2) Push two hook of the guide suction and lift up the rear

of noise filter ass'y.

3) Disconnect lead wires from H.V. capacitor and

remove screw securing the H.V. diode earth wire to
the back plate.

4) Disconnect each lead wires from the AC relay and the

fan motor.

5) Remove two screws securing the guide suction ass'y

to the back plate and lift up the guide suction ass'y.

6) Remove one screw from H.V. capacitor bracket.

7) Pull H.V. capacitor bracket from the guide suction.

8) Remove the fan from the fan motor.

9) Remove two screws securing the fan motor to the 

guide suction and lift it up.

1) Disconnect the wire leads from oven lamp.

2) Remove one screw securing the Air Duct to the

magnetron.

3) Push hook to right and left of Air Duct with dirve.

4) Lift the oven lamp up.

1) Disconnect the wire leads from the transformer to the

magnetron, C-protector assembly.

2) Remove four screws securing the H.V. transformer to

the base plate.

3) Lift the H.V. transformer up.

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.

15

H.V. Transformer

1) Remove the turntable.

2) Remove the turntable shaft VERY CAREFULLY with

a slotted screw driver.

3) Lay the set down on its back.

4) Remove the turntable motor cover. The turntable

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

5) Disconnect the lead wires from the turntable motor

terminals.

6) Remove two screws securing the turntable motor to

the oven cavity assembly.

7) Lift the turntable motor and mount turntable motor.

8) After repairing the motor, fit the turntable motor

cover's projecting part to the base plate's slit.

1) INTERLOCK MECHANISM

The door lock mechanism is a device which has been
specially designed to completely eliminate 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 AND

SECONDARY SWITCH 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. (1/64inch)
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/secondary
switch operate properly by following the continuity
test procedure.

16

PRIMARY

SWITCH

MONITOR

SWITCH

SECONDARY

SWITCH

ADJUSTMENT 

DIRECTION

When the door button is slowly depressed with the
door closed, an audible "click" should be heard at
the same time or successively at intervals. When
the button is slowly released, 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 adjustment procedure. Disconnect
the wire lead from the primary switch. Connect the
multimeter 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 multimeter leads to the common (COM)
and normally open (NO) terminals of the switch. The
meter should indicate a 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 multimeter leads to the common (COM)
and normally close (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 closed circuit.When the monitor switch
operation is abnormal, replace the same type of
switch.

17

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

COM  

NO

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