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23

To remove the outer case, proceed as follows.
1. Disconnect oven from power supply.
2. Open the oven door and wedge it open.
3. Remove the two (2) screws from the lower portion of the

rear cabinet and lower left portion of the oven cabinet
back side using by special screw drive (Type; LHSTIX
DLR4-100T).

4. Remove the screws from rear and along the side edge

of case.

5. Slide the entire case back about 3cm to free it from

retaining clips on the cavity face plate.

6. Lift the entire case from the oven.
7. Remove the screws holding the rear cabinet to the

oven.

8. Remove the rear cabinet.
9. Discharge the HV capacitor before carrying out any

further work.

10. Do not operate the oven with the outer case removed.

N.B.; Step 1,2 and 9 form the basis of the 3D checks.

CAUTION:DISCHARGE HIGH VOLTAGE CAPACI-

TOR BEFORE TOUCHING ANY OVEN
COMPONENTS OR WIRING.

1. CARRY OUT 3D CHECKS.
2. Make sure that a definite” click” can be heard when the

microwave oven door is unlatched. (Hold the door in
a closed position, then pull the door release lever with
one hand, this causes the latch leads to rise, it is then
possible to hear a “click’ as the door switches oper-
ate.)

3. Visually check the door and cavity face plate for

damage (dents, cracks, signs of arcing etc.).

Carry out any remedial work that is necessary before

operating the oven.

Do not operate the oven if any of the following conditions

exist;

1. Door does not close firmly.
2. Door hinge, support or latch hook is damaged.
3. The door gasket or seal or damaged.
4. The door is bent or warped.
5. There are defective parts in the door interlock system.
6. There are defective  parts in the microwave generating

and transmission assembly.

7. There is visible damage to the oven.

Do not operate the oven:
1. Without the RF gasket (Magnetron).
2. If the wave guide or oven cavity are not intact.
3. If the door is not closed.
4. If the outer case (cabinet) is not fitted.

Please refer to ‘OVEN PARTS, CABINET PARTS, DOOR PARTS’, when carrying out any of the following removal
procedures:

Special screw

CAUTION
1. DO NOT REPLACE ONLY HIGH VOLTAGE REC-

TIFIER. WHEN REPLACE IT, REPLACE HIGH
VOLTAGE RECTIFIER ASSEMBLY.

2. WHEN REPLACING HIGH VOLTAGE RECTIFIER

ASSEMBLY, ENSURE THAT THE CATHODE
(EARTH) CONNECTION IS SECURELY FIXED
TO THE CHASSIS WITH A EARTHING SCREW.

6. Now, the two (2) high voltage capacitors are free.

To remove the components, proceed as follows.
1. CARRY OUT 3D CHECKS.
2. Remove two (2) screws holding earth side terminals of

high voltage rectifier assemblies.

3. Disconnect all the leads and terminals of high voltage

rectifier assembly from high voltage capacitor.

4. Remove two (2) screws holding capacitor holder to the

right side of oven cavity and remove the capacitor
holder.

5. Now, high voltage rectifier assembly should be free.

Screw Driver
(Type; LHSTIX DLR4-100T)

24

1. Remove the outer case cabinet referring to "OUTER

CASE REMOVAL" and CARRY OUT 3D CHECKS.

2. Remove the eleven (11) screws holding the rear

cabinet to the oven cavity.

3. Disconnect the power supply cord from the noise filter.
4. Remove the one (1) screw holding the earth wire of the

power supply cord to the noise filter angle.

5. Remove the rear cabinet with the power supply cord

from the oven cavity.

6. Remove the two (2) screws holding the magnetron

exhaust duct to upper and lower waveguide.

7. Disconnect all the wire leads from the two (2)

magnetrons.

8. Carefully remove each four (4) screws holding each

two (2) magnetrons to waveguide. When removing
the screws hold the magnetron to prevent it from
falling.

9. Remove the magnetron from the waveguide with care

so the magnetron antenna is not hit by any metal
object around the antenna.

4. Now, the magnetron is free.

CAUTION: WHEN REPLACE THE MAGNETRON,

BE SURE THE R.F. GASKET IS IN PLACE
AND THE MAGNETRON MOUNTING
SCREWS TIGHTENED SECURELY.

1. Remove the outer case cabinet referring to "OUTER

CASE REMOVAL" and CARRY OUT 3D CHECKS.

2. Disconnect the all wire leads from the magnetron(s).
3. Remove the wire holder holding the high voltage

wires.

4. Disconnect all wire leads from the high voltage

transformer(s).

5. Remove the each two (2) screws holding each high

voltage transformer.

6. Now, high voltage transformer(s) is (are) free.

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

the blower motor thermal cut-out.

3. Remove the one (1) screw holding the blower motor to

the oven cavity.

4. Remove the one (1) screw holding the blower motor to

the chassis support.

5. Remove the blower motor.  Now, the blower motor is

free.

1. Remove the outer case cabinet referring to "OUTER

CASE REMOVAL" and CARRY OUT 3D CHECKS.

2. Disconnect the wire leads from the stirrer motor (up-

per).

3. Remove the one (1) screw holding the stirrer motor

(upper) to the oven cavity.

4. Turn and lift up the stirrer motor (upper).
5. Now, the stirrer motor (upper) is free.

Oven lamp
socket

Terminal

Wire lead

Flat type small 
screw driver

Terminal hole

1. CARRY OUT 3D CHECKS.
2. Remove the oven lamp.
3. Pull the wire leads from the oven lamp socket by

pushing the terminal hole of the oven lamp socket with
the flat type small screw driver.

4. Lift up the oven lamp socket.
5. Now, the oven lamp socket is free.

1. Disconnect oven from the power supply.
2. Remove the stirrer motor cover by snipping off the

material in four portions.

3. Where the portions have been snipped off bend the

portions flat. No sharp edge must be evident after
removal of the stirrer cover.

4. Disconnect wire leads from the stirrer motor. (See

"Positive lock connector removal")

5. Remove one (1) screw holding the stirrer motor to

oven cavity.

6. Now, the stirrer motor (lower) is free.
7. After replacement use the one (1) screw to fit the stirrer

motor cover. (This screw has been fitted to the base
plate near the stirrer motor cover beforehand.)

25

The complete control panel should be removed for re-
placement of components. To remove the control panel,
proceed as follows:

1. CARRY OUT 3D CHECKS.
2. Remove the air intake filter assembly from the base

plate.

3. Remove two (2) screws holding the control panel to

the base plate.

4. Pull down the control panel and remove it forward.
5. Disconnect two connectors (A), (B), (D), (H) and  TAB

terminal (TAB1,2,3,4) from the control unit.

6. Now the control panel assembly is free.

1)  Hold the lower end (Position A, Fig. 1) of the touch

control panel assembly firmly while sliding it down and
toward you.

2) If the Touch Control Panel is hard to remove;
(1) Insert a flat head screw driver into space  B . (Fig. 1)
(2) Rotate the screwdriver clockwise while holding posi-

tion  C of the Touch Control Panel. (Fig. 2)

(3) Re-solder the Relay (RY-4) prior to reinstalling the

Touch Control Panel.

B

A

C

B

Fig. 1

Fig. 2

TOUCH CONTROL PANEL

SCREW DRIVER

Replacement of individual component is as follows:

7. Remove two (2) screws holding the control panel

mounting angle to the panel frame.

8. Lift up the control panel mounting angle from the panel

frame.

9. Remove six (6) screws holding the control unit to the

panel frame assembly.

10.Push down the right side two (2) hooks fixing the

control unit to the panel frame assembly, and lift up the
control unit upward.

11.Now, the control unit and control panel frame (with

switch unit) are free.

12.Remove the three (3) screws holding the switch unit

(Main) to the control panel frame.

13.Remove the two (2) screws holding the  switch unit

(Sub.) to the control panel frame.

14.Now,  the switch unit is free

12.Remove the  two (2) screws holding the earth wire to

the rotary encoder and control panel mounting angle.

13.Remove the two (2) screws holding the  rotary encoder

to the control panel frame.

14.Remove the knob from the rotary encoder shaft.
15.Now,  the rotary encoder is free.

Procedure
1. Pushing the lever of positive lock

®

 connector.

2. Pull down the connector from the terminal.
3. Now, the connector is free.

Note: If the positive lock

®

 has a insulation sleeve, first

remove it. If you do not so, you can not push the
lever of positive lock

®

.

CAUTION: The positive lock

®

 terminal can not be dis-

connected by only pulling. Because once
you (Service personnel) have connected the
positive lock

®

 connector to the terminal, the

positive lock

®

  connector has been locked.

Terminal

Push

Pull down

1

2

Lever

Positive lock®

connector

26

1.

CARRY OUT 3D CHECKS.

2.

Release the cord bushing from the rear cabinet.

3.

Disconnect the brown and blue wires of the power
supply cord from the noise filter.

4.

Loosen the single (1) screw holding the earth angle
and earth wire of power supply cord.

5.

Remove the power supply cord.

CAUTION: DO NOT ALLOW THE WIRE LEADS OF

THE POWER SUPPLY CORD TO COME
NEAR THE HIGH VOLTAGE TRANS-
FORMER. BECAUSE THE HIGH VOLT-
AGE TRANSFORMER BECOMES HOT.

Re-install
1.

Insert the power supply cord into the cord bushing.

2.

Connect the brown and blue wires of power supply
cord into the terminals of noise filter, referring to
pictorial diagram.

3.

Insert the green/yellow wire of power supply cord
into the earth angle, and tight the screw holding the
earth angle.

4.

Re-install the cord bushing to the rear cabinet.

5.

Re-install the rear cabinet to oven cavity and the
bottom plate with the eleven (11) screws and two (2)
washers.

6.

CARRY OUT 4R CHECKS.

latch hook.

6. For 1st latch and stop switches removal

6-1. Disconnect the wire leads from the 1st latch and

stop switches.

6-2. Remove the single (1) screw and nut holding the

1st latch and stop switches to the latch hook.

CAUTION: WHEN THE 1ST LATCH SWITCH AND

2ND. LATCH SWITCH ARE INSTALLED,
THE TWO (2) TABS OF THE LATCH
HOOK SHOULD BE BROKEN.

1. CARRY OUT 3D CHECKS.
2. Remove the control panel from the oven cavity refer-

ring to “CONTROL PANEL REMOVAL”.

3. Remove the two (2) screws holding the latch hook to

the oven cavity.

4. Open the door and pull the latch hook out of the oven

cavity.

5. For 1st latch, 2nd latch or Monitor switch removal

5-1. Disconnect the wire leads from the switch.
5-2. Push the retaining tabs outward slightly and then

pull the switch forwards and remove it from the

In case 1st latch switch, 2nd latch, stop switch, 3rd latch
switch and monitor switch do not operate properly due to a
mis-adjustment, the following adjustment should be made.
1. Loosen the two (2) screws holding the latch hook.
2. 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
0.5mm. The vertical position of the latch hook should be
placed where the stop switch and 1st, 2nd, 3rd latch
switches have activated with the door closed.
The horizontal position of the latch hook should be
placed where the monitor switch has activated with the
door closed.

3. Secure the screws with washers firmly.
4. Make sure of the 1st, 2nd, 3rd latch switches, stop

switch, and monitor switch operation. If those switches
have not activated with the door closed, loose two (2)
screws holding latch hook and adjust the latch hook
position.

After adjustment, make sure of the following:
1. The stop switch and 1st, 2nd, 3rd latch switches interrupt

the circuit before the door open when the door release
lever is pulled, and then and monitor switch close the

circuit when the door is opened.

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

around the door with an approved microwave survey

meter. (Refer to Microwave Measurement Procedure.)

Latch head

Monitor switch

Latch hook

1st. latch switch

2nd. latch switch

Stop switch

3rd. latch switch

Latch head

Joint lever

Door release
lever

Latch lever

N

Screw

Green/Yellow 
wire

Cord
bushing

Rear 
cabinet

Power
supply 
cord

Blue wire

Brown wire

Noise filter unit

L

WHT

BLK