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11 – 4

1. Insert the moulding cord stopper of power supply cord into the

square hole of the rear cabinet, referring to the Figure C-3 (b).

2. Install the earth wire lead of power supply cord to the oven cavity

back plate with one (1) screw and tight the screw.

3. Connect the brown and blue wire leads of power supply cord to the

noise filter correctly, referring to the Pictorial Diagram.

                      Figure C-3(a) Power Supply Cord Replacement                                      Figure C-3(b) Power Supply Cord Replacement

1. CARRY OUT 3D CHECKS.

2. Disconnect the leads from the control unit.

3. Remove the one (1) screw holding the control panel to the front

panel of the oven cavity.

4. Lift up the control panel assembly and release it from the oven cav-

ity.

5. Now, the control panel assembly is free.

1. CARRY OUT 3D CHECKS.

2. Remove the control panel assembly, referring to chapter of CON-

TROL PANEL ASSEMBLY REMOVAL.

3. Disconnect the ribbon cable of the membrane switch from the con-

nector (CN-G) on the control unit.

4. Tear away the graphic sheet from the control panel frame.

5. Tear away the membrane switch from the control panel frame.

1. Remove remaining adhesive on the control panel frame surfaces

with a soft cloth soaked in alcohol.

2. Tear the backing paper from the new membrane switch.

3. Insert the ribbon cable of the membrane switch into the slit of the

control panel frame.

4. Adjust the upper edge and right edge of the membrane switch to

the small depression on the surface of the control panel frame. 

5. Attach the membrane switch to the control panel frame by rubbing

with a soft cloth not to scratch.

6. Tear the backing paper from the new graphic sheet.

7. Adjust the upper edge and right edge of the graphic sheet to the

large depression on the surface of the control panel frame. 

8. Attach the graphic sheet to the control panel frame by rubbing with

a soft cloth not to scratch.

9. Connect the ribbon cable of the membrane switch to the connector

(CN-G) on the control unit.

NOTE: Do not contact the contact surface of the ribbon cable

Figure C-4. Graphic Sheet and Membrane Switch Replacement

N

L

Power Supply

Cord

Oven Cavity

Back Plate

Screw

Green/Yellow

Wire

Brown Wire

Blue

Wire

Noise Filter

WHT

RED

P ower S upply
C ord

O ven C avity
B ack P late

S quare
Hole

Moulding
C ord S topper

Graphic sheet

Ribbon

cable

Connector

(CN-G)

Small depression

Control panel frame

Slit

Control unit

Membrane

switch

Ribbon

cable

Large

depression

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11 – 5

1. CARRY OUT 3D CHECKS.

2. Remove the control panel assembly, referring to section of CON-

TROL PANEL ASSEMBLY REMOVAL.

3. Disconnect wire leads from the switches.

4. Remove two (2) screws holding latch hook to oven flange.

5. Remove latch hook assembly from oven flange.

6. Push outward on the two (2) retaining tabs holding switch in place.

7. Switch is now free.

1. Re-install each switch in its place. The 1st. latch switch and the

monitor switch are in the lower position and the 2nd. interlock relay
control switch is in the upper position.

2. Secure latch hook (with two (2) mounting screws) to oven flange.

3. Re-connect wire leads to each switch. Refer to pictorial diagram.

4. Reinstall the control panel assembly to the oven cavity.

5. Reconnect wire leads to the control unit, referring to the pictorial

diagram. 

6. Make sure that the monitor switch is operating properly and check

continuity of the monitor circuit. Refer to chapter “Test Procedure”
and Adjustment procedure.

1. CARRY OUT 3D CHECKS.

If the 1st. latch switch, 2nd. interlock relay control switch and monitor
switch do not operate properly due to a misadjustment, the following
adjustment should be made.

2. Loosen the two (2) screws holding latch hook to the oven cavity

front flange.

3. With door closed, adjust latch hook by moving it back and forth,

and up and down. In and out play of the door allowed by the upper
and lower position of the latch hook should be less than 0.5mm.
The vertical position of the latch hook should be adjusted so that
the 1st. latch switch and 2nd. interlock relay control switch are acti-
vated with the door closed. The horizontal position of the latch hook
should be adjusted so that the plunger of the monitor switch is
pressed with the door closed.

4. Secure the screws with washers firmly.

5. Check the operation of all switches. If each switch has not activated

with the door closed, loosen screw and adjust the latch hook posi-
tion.

1. In and out play of door remains less than 0.5mm when in the

latched position. First check upper position of latch hook, pushing
and pulling upper portion of door toward the oven face. 

Then check lower portion of the latch hook, pushing and pulling
lower portion of the door toward the oven face. Both results (play in
the door) should be less than 0.5mm.

2. When the door is open, the contacts of the 1st. latch switch and

2nd. interlock relay control switch open.

3. Monitor switch contacts close when door is opened.

4. Re-install outer case and check for microwave leakage around

door with an approved microwave survey meter. (Refer to Micro-
wave Measurement Procedure.)

                          Figure C-5. Latch Switch Adjustments

1. Disconnect the power supply cord.

2. Open the door slightly.

3. Insert a putty knife (thickness of about 0.5mm) into the gap

between the choke cover and corner portion of door panel as
shown in Figure C-6 to free engaging parts.

4. Pry the choke cover by inserting a putty knife as shown Figure C-6.

5. Release choke cover from door panel.

6. Now choke cover is free.

NOTE: When carrying out any repair to the door, do not bend or

                               Figure C-6. Door Disassembly

2nd. Interlock

Relay Control

Switch

1st. Latch Switch

Latch

Heads

Door

Switch Lever

Latch Hook

Monitor Switch

Choke Cover

Door Frame

Putty Knife

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11 – 6

7. Release two (2) pins of door panel from two (2) holes of upper and

lower oven hinges by lifting up.

8. Now, door panel with door frame is free from oven cavity.

9. Release door panel from ten (10) tabs of door frame and remove

the door frame by sliding the door panel downward.

10.Now, door panel with sealer film is free.

11.Tear sealer film from door panel.

12.Now, door panel is free.

13.Slide latch head upward and remove it from door frame with releas-

ing latch spring from door frame and latch head.

14.Now, latch head and latch spring are free.

15.Remove the two (2) screw holding the door handle and the glass

stopper to the door frame.

16.Remove the door handle and the glass stopper from the door

frame.

17.Remove the door glass from the door frame by sliding the door

glass rightwards.

18.Now, door glass is free.

1. Insert door glass into the door frame by sliding leftwards.

2. Re-install the glass stopper and the door handle to the door frame

with the two (2) screws.

3. Re-install latch spring to the head. Re-install latch spring to the

door frame. Re-install latch head to the door frame.

4. Re-install door panel to door frame by fitting ten (10) tabs of door

frame to ten (10) holes of door panel.

5. Put sealer film on door panel. Refer to “Sealer Film” about how to

handle new one.

6. Catch two (2) pins of door panel on two (2) hole of upper and lower

oven hinges

7. Re-install choke cover to door panel by pushing.

NOTE: After any service to the door;

1) Make sure that 1st. latch switch, 2nd. interlock relay control

2) An approved microwave survey meter should be used to

1. Door latch heads smoothly catch latch hook through latch holes

and that latch head goes through center of latch hole.

2. Deviation of door alignment from horizontal line of cavity face plate

is to be less than 1.0mm.

3. Door is positioned with its face pressed toward cavity face plate.

4. Check for microwave leakage around door with an approved micro-

wave survey meter. (Refer to Microwave Measurement Procedure).

NOTE: The door on a microwave oven is designed to act as an

           Figure C-7. Door Replacement

1. Put the adhesive tape on the backing film of the sealer film as

shown in Fig. C-8

2. Tear the backing film by pulling the adhesive tape.

3. Put the pasted side of the sealer film on the door panel

                              Figure C-8. Sealer film

Upper Oven

Hinge

Lower

Oven Hinge

Pin

Upper

Oven Hinge

Slit choke of

door panel

Choke Cover

Pin

Lower Oven

Hinge

Sealer film

Backing film

Adhesive tape

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12 – 1

R269WM

Service Manual

 

After any repair, the microwave oven must be checked for microwave leakage to ensure continued safe operation. BS EN 60335-2-25 specifies that
the maximum permitted leakage with a load of 275 ml is 50 W/m

2

 (equivalent to 5 mW/cm

2

) at a distance of 5 cm from the oven.

The following items are required to carry out this test:

1. A low form of 600 ml beaker made from an electrically non-conductive material, such as glass or plastic, with an inside diameter of approximately

8.5 cm. This must contain 275 

± 15 ml of water, at an initial temperature of 20 ± 2°C.

2. A leakage detector which has been calibrated within the preceding 12 months to a stand whose accuracy can be traced to National Physical Lab-

oratory Standards.

Recommended instruments are:-

Apollo “XI”

Celtec “A100”

Before commencing the test, check that the leakage detector is functioning and adjusted according to the manufacturer's instructions, and any spac-
ers are fitted to ensure that measurement is taken 5cm from the surface of the oven.

1. Place the beaker containing the water load in the oven cavity at the centre of the turntable. The placing of this standard load in the oven is impor-

tant, not only to protect the oven, but also to ensure that any leakage it is not disguised by too large a load absorbing energy.

2. 2.Close the oven door, and with the power level set to FULL, turn the oven ON with the timer set for a few minutes operation. Should the water

begin to boil before the test has been completed, it should be replaced.

3. 3.As shown in the diagram below, move the probe slowly (not faster than 2.5 cm/sec.);-

1) around the edge of the door following the gap

2) across the face of the door

3) across any vents in the oven's sides, rear or top

Dotted line indicates the path taken by the leakage detector.

Dotted line indicates the path

taken by the leakage detector.