Sharp R820bk Service Manual

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R-820BK
R-820BW
1. Precautions for Handling Electronic Components
This unit uses CMOS LSI in the integral part of the circuits.
When handling these parts, the following precautions should
be strictly followed. CMOS LSI have extremely high
impedance at its input and output terminals. For this reason,
it is easily influenced by the surrounding high voltage power
source, static electricity charge in clothes, etc., and
sometimes it is not fully protected by the built-in protection
circuit.
In order to protect CMOS LSI.
1) When storing and transporting, thoroughly wrap them in
aluminium foil. Also wrap PW boards containing them in
aluminium foil.
2) When soldering, ground the technician as shown in the
figure and use grounded soldering iron and work table.
approx. 1M ohm
2. Shapes of Electronic Components
3. Servicing of Touch Control Panel
We describe the procedures to permit servicing of the touch
control panel of the microwave oven and the precautions
you must take when doing so.
To perform the servicing, power to the touch control panel
is available either from the power line of the oven itself or
from an external power source.
(1) Servicing the touch control panel with power
supply of the oven :
CAUTION:
THE HIGH VOLTAGE TRANSFORMER OF THE
MICROWAVE OVEN IS STILL LIVE DURING SERV-
ICING AND PRESENTS A HAZARD .
T
herefore, before checking the performance of the touch
control panel,
1) Disconnect the power supply cord, and then remove
outer case.
2) Open the door and block it open.
3) Discharge high voltage capacitor.
4) Disconnect the leads to the primary of the power trans-
former.
5) Ensure that these leads remain isolated from other
components and oven chassis by using insulation tape.
6) After that procedure, re-connect the power supply cord.
After checking the performance of the touch control panel,
1) Disconnect the power supply cord.
2) Open the door and block it open.
3) Re-connect the leads to the primary of the power trans-
former.
4) Re-install the outer case (cabinet).
SERVICING
5) Re-connect the power supply cord after the outer case is
installed.
6) Run the oven and check all functions.
A. On some models, the power supply cord between the
touch control panel and the oven itself is so short that the
two cant be separated.
For those models, check and repair all the controls
(sensor-related ones included) of the touch control panel
while keeping it  connected to the oven.
B. On some models, the power supply cord between the
touch control panel and the oven proper is long enough
that they may be separated from each other. For those
models, therefore, it is possible to check and repair the
controls of the touch control panel while keeping it apart
from the oven proper; in this case you must short both
ends of the door sensing switch (on PWB) of the touch
control panel with a jumper, which brings about an
operational state that is equivalent to the oven door being
closed. As for the sensor-related controls of the touch
control panel, checking them is possible if the dummy
resistor(s) with resistance equal to that of the controls are
used.
(2) Servicing the touch control panel with power
supply from an external power source:
Disconnect the touch control panel completely from the
oven proper, and short both ends of the door sensing
switch (on PWB) of the touch control panel, which brings
about an operational state that is equivalent to the oven
door being closed. Connect an external power source to
the power input terminal of the touch control panel, then
it is possible to check and repair the controls of the touch
control panel; it is also possible to check the sensor-
related controls of the touch control panel by using the
dummy resistor(s).
4. Servicing Tools
Tools required to service the touch control panel assembly.
1) Soldering iron: 30W
(It is recommended to use a soldering iron with a
grounding terminal.)
2) Oscilloscope: Single beam, frequency range: DC -
10MHz type or more advanced model.
3) Others: Hand tools
5. Other Precautions
1) Before turning on the power source of the control unit,
remove the aluminium foil applied for preventing static
electricity.
2) Connect the connector of the key unit to the control unit
being sure that the lead wires are not twisted.
3) After aluminium foil is removed, be careful that abnormal
voltage due to static electricity etc. is not applied to the
input or output terminals.
4) Attach connectors, electrolytic capacitors, etc. to PWB,
making sure that all connections are tight.
5) Be sure to use specified components where high
precision is required.
ECB
ECB
Transistor
2SB1238Transistor
DTD143ES 
						

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To remove the outer case, proceed as follows.
1. Disconnect the power supply cord.
2. Open the oven door and block it open.
3. Remove the two (2) screws (LHSTIX screws) holding the
back plate to the oven cavity rear plate, by using LHSTIX
screw driver (LHSTIX LR-4).
4. Remove the back plate with the sub back plate.5. Remove the two (2) screws from the lower portion of the
rear cabinet using a T20H Torx type or GTXH20-100
screw driver.
6. Remove the remaining three (3) screws from rear and
along the side edge of case.
7. Slide the entire case back about 3cm to free it from
retaining clips on the cavity face plate.
Microwave ovens contain circuitry capable of producing very high voltage and current, contact with following parts may
result in severe, possibly fatal, electric shock.
(Example)
High Voltage Capacitor, Power Transformer, Magnetron, High Voltage Rectifier Assembly,  High Voltage Harness etc..
WARNING:Avoid possible exposure to microwave energy. Please follow the instructions below before
operating the oven.
WARNING AGAINST HIGH VOLTAGE:
OUTER CASE REMOVAL
COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE
To prevent an electric shock, take the following pre-
cautions.
1. Before wiring,
1) Disconnect the power supply cord.
2) Open the door and block it open.
3) Discharge the high voltage capacitor and wait for 60
seconds.
2. DonÕt let the wire leads touch to the followiong parts;
1) High voltage parts:
Magnetron, High voltage transformer, High voltage
capacitor and High voltage rectifier assembly.
2) Hot parts:
Oven lamp, Magnetron, High voltage transformer,
grill heater, bottom heater and Oven cavity.
WARNING FOR WIRING
1. Disconnect the power supply cord.
2. Make sure that a definite click can be heard when the
microwave oven door is unlatched. (Hold the door in a
closed position with one hand, then push the door open
button with the other, this causes the latch leads to rise,
it is then possible to hear a click as the door switches
operate.)
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 is 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.
3) Sharp edge:
Bottom plate, Oven cavity, Waveguide flange,
Chassis support and other metallic plate.
4) Movable parts (to prevent a fault)
Fan blade, Fan motor, Switch, Switch lever, Open
button.
3. Do not catch the wire leads in the outer case cabinet.
4. Insert the positive lock connector until its pin is locked
and make sure that the wire leads do not  come off even
if the wire leads are pulled.
5. To prevent an error function, connect the wire leads
correctly, referring to the Pictorial Diagram.
Please refer to ÔOVEN PARTS, CABINET PARTS, CONTROL PANEL PARTS, DOOR PARTSÕ, when carrying out any of
the following removal procedures: 
						

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POWER TRANSFORMER REMOVAL
6. Disconnect the main wire harness from the power
transformer.
7. Remove the two (2) screws  holding the transformer to
base plate.
8. Remove the transformer.
9. Now the power transformer is free. 1. Disconnect the power supply cord and then remove
outer case.
2. Open the oven door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect the filament leads of power transformer from
high voltage capacitor and the magnetron.
5. Disconnect the H.V. wire B from the power transformer. 8. Lift the entire case from the oven.
9. Discharge the H.V. capacitor before carrying out any
further work.
10.Do not operate the oven with the outer case removed.
CAUTION: 1. DISCONNECT OVEN FROM POWER SUP
PLY BEFORE REMOVING OUTER CASE.
2. DISCHARGE THE HIGH VOLTAGE CA-
PACITOR BEFORE TOUCHING ANY OVEN
COMPONENTS OR WIRING.
NOTE: When replacing the outer case, the 2 special
Torx screws must be reinstalled in the same
locations.
HIGH VOLTAGE RECTIFIER ASSEMBLY AND HIGH VOLTAGE CAPACITOR REMOVAL
To remove the components, proceed as follows.
1. Disconnect the power supply cord and then remove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect H.V. wire of the high voltage rectifier assembly
from the magnetron.
5. Disconnect all the leads and terminals of high voltage
rectifier assembly from the high voltage capacitor.
6. Remove one (1) screw holding earth side terminal of the
high voltage rectifier assembly.7.Now, the high voltage rectifier assembly should be free.
8. Remove one (1) screw holding capacitor holder to the
oven cavity rear plate.
9. Release the capacitor holder from the fan duct.
10.Remove the capacitor from the capacitor holder.
11.Now, the capacitor should be free.
CAUTION: WHEN REPLACING HIGH VOLTAGE RECTI-
FIER AND HIGH VOLTAGE CAPACITOR,
GROUND SIDE TERMINAL OF THE HIGH
VOLTAGE RECTIFIER MUST BE SECURED
FIRMLY WITH A GROUNDING SCREW.
1. Disconnect the power supply cord and remove outer
case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Release the tabs of air intake duct from the chassis
support and the oven cavity.
5. Disconnect the high voltage wire of the high voltage
rectifier assembly and filament lead of the transformer
from the magnetron.
6. Remove the one (1) screw holding the chassis support
to the magnetron.
MAGNETRON REMOVAL
7. Move the air intake duct to the left.
8. Carefully remove four (4) screws holding magnetron 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.
CAUTION: WHEN REPLACING THE MAGNETRON, BE
SURE THE R.F. GASKET IS IN PLACE AND
THE MAGNETRON MOUNTING SCREWS
ARE TIGHTENED SECURELY.
CONTROL PANEL ASSEMBLY
1.
Disconnect the power supply cord and then remove outer
case.
CONTROL PANEL ASSEMBLY REMOVAL
2. Open the door and block it open.
3. Discharge high voltage capacitor.
LHSTIX 
Screw 
Driver(Size LR-4) LHSTIX ScrewBack Plate Outer Case Cabinet
Sub Back Plate
Special 
screw
Screw Driver
(Type: TORX T20 H or 
GTXH20-100) 
						

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POSITIVE LOCK¨  CONNECTOR (NO-CASE TYPE) REMOVAL
Figure C-2.  Positive lock¨ connector 1. Disconnect the power supply cord and then remove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Push the lever of positive lock
¨ connector.
5. Pull down on the positive lock¨ connector.
CAUTION: WHEN CONNECTING THE POSITIVE LOCK
¨
CONNECTORS TO THE TERMINALS, IN-
STALL THE POSITIVE LOCK¨ SO THAT THE
LEVER FACES YOU
Oven lamp
socket
Terminal
Wire lead
Terminal hole
Flate type small
screw driver
Terminal
Push
Pull down4
5
Lever Positive lock®
connector
1. Disconnect the power supply cord and then remove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Lift up the oven lamp socket from air intake duct.
5. Pull the wire leads from the oven lamp socket by  pushing
the terminal hole of the oven lamp socket with the small
flat type screw driver.
6. Now, the oven lamp socket is free.
OVEN LAMP AND LAMP SOCKET REMOVAL
Figure C-1. Oven lamp socket
TURNTABLE MOTOR REMOVAL
1. Disconnect the power supply cord.
2. Remove the turntable motor cover by snipping of material
in four corners.
3. Where the corners have been snipped off, bend corner
areas flat. No sharp edge must be evident after removal
of turntable motor cover.
4. Disconnect the wire leads from the turntable motor andremove the two (2) screws holding the turntable motor.
5. Now, the turntable motor is free.
6. After replacement use  the one (1) screw provided with
the turntable motor assembly to fit turntable motor cover.
NOTE: The one (1) screw to fit the turntable motor cover
should be XFPSD40P12K00, XFPSD40P10K00 or
XFPSD40P08K000. 4. Disconnect the main wire harness, thermistor harness and
the switch harness from the power unit.
5. Straighten the tab of the oven cavity front flange holding
the tab of the control panel frame.
6. Lift up the control panel assembly.
7. Now, the control panel assembly is free.
CONTROL UNIT
8.
Disconnect the flat ribbon cable from the connector CN-G.
9. Remove the two (2) screws holding the CPU unit to the
control panel frame.
10.Release the four (4) tabs of the control panel frame
holding the CPU unit to the control panel frame.
11.Release the liquid crystal display (LCD) from  the LCD
holder.
12.Now, the LCD sheet is free.
13.Release the two (2) tabs of the LCD holder holding theCPU unit to the LCD holder.
14.Remove the LCD holder from the CPU unit.
15.Remove the two (2) screws holding the power unit to the
control panel frame.
16.Release the four (4) tabs of the control panel frame
holding the power unit to the control panel frame.
17.Now, the control unit (CPU unit + Power unit) is free.
NOTE: 1.Before attaching a new key unit, wipe off  remaining
adhesive on the control panel frame surfaces
completely with a soft cloth soaked in alcohol.
2. When attaching the key unit to the control panel
frame, adjust the upper edge and right edge of
the key unit to the correct position of  control panel
frame.
3. Stick the key unit firmly to the control panel frame
by rubbing with soft cloth not to scratch. 
						

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COOLING FAN MOTOR REMOVAL
REMOVAL
1.
Disconnect the power supply cord and then remove outer
case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect the wire leads from the fan motor.
5. Remove the one (1) screw  holding the capacitor holder
to the oven cavity rear plate.
6. Remove the one (1) screw holding the fan duct to the
oven cavity rear plate.
7. Release the tabs of the capacitor holder from fan duct.
8. Remove the fan duct from the oven.
9. Remove the fan blade from the fan motor shaft according
to the following procedure.
10.Hold the edge of the rotor of the fan motor by using a pair
of groove joint pliers.
CAUTION:
* Make sure that no metal pieces enter the gap
between the rotor and the stator of the fan motor
because the rotor is easily shaven by pliers and
metal pieces may be produced.
* Do not touch the pliers to the coil of the fan motor
because the coil may be cut or injured.
* Do not disfigure the bracket by touching with the
pliers.
11.Remove the fan blade from the shaft of the fan motor by
pulling and rotating the fan blade with your hand.
12. Now, the fan blade will be free.CAUTION:
* Do not reuse the removed fan blade because the
hole (for shaft) may be larger than normal.
13.Remove the two (2) screws holding the fan motor to the
fan duct.
14.Now, the fan motor is free.
INSTALLATION
1. Install the fan motor to the fan duct with the two (2)
screws.
2. Install the fan blade to the fan motor shaft according to
the following procedure.
3. Hold the center of the bracket which supports the shaft
of the fan motor on the flat table.
4. Install the fan blade to the shaft of fan motor by pushing
the fan blade with a small, light weight, ball peen hammer
or rubber mallet.
CAUTION:
* Do not hit the fan blade hard when installing because
the bracket may be disfigured.
* Make sure that the fan blade rotates smooth after
installation.
* Make sure that the axis of the shaft is not slanted.
5. Install the fan duct to the oven cavity rear plate with the
one (1) screw.
6. Insert the tabs of the capacitor holder to the fan duct.
7. Install the capacitor holder to the oven cavity rear plate
with the one (1) screw.
8. Re-connect the wire leads to the fan motor.
Side View Rear View
Shaft
TableCenter of
bracket
Gap
Rotor Bracket StatorGroove joint pliers
Coil
Shaft
Axis
Stator
Rotor
These are the positions 
that should be pinched 
with pliers
1.Disconnect the power supply cord and then remove outer
case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Now, the back plate with the sub back plate should be
removed.
5. Disconnect the wire leads from the convection motor.
6. Remove the two  (2) screws  holding the conv. thermal
cover to the oven cavity rear plate.
7. Remove the four (4) screws holding the convection
duct to the oven cavity rear plate.
8. Remove the convection duct assembly from the oven
cavity rear plate.
9. Remove the one (1) nut and the two  (2) washers  holding
the convection fan to the convection motor shaft.
10.Remove the convection fan.
CONVECTION MOTOR REMOVAL
11.Remove the three  (3) screws  holding the convection
duct to the conv. thermal cover.
12.Remove the convection duct with the conv. air angles
from the conv. thermal cover.
13.Remove the thermal insulation.
14.Remove the one  (1) pipe  holding the cooling fan to the
convection motor shaft.
15.Remove the cooling fan and the one  (1) washer from the
convection motor shaft.
16.Remove the two (2) screws holding the convection motor
to the conv. thermal cover.
17.Remove the convection motor from the conv. thermal
cover.
18.Remove the one  (1) ring from the convection motor
shaft.
19.Now, the convection motor is free. 
						

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DOOR SENSING SWITCH/SECONDARY INTERLOCK SWITCH AND MONITOR SWITCH REMOVAL
1. Disconnect the power supply cord and then remove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Now, the back plate with the sub back plate should be
removed.
5. Disconnect the connector CN-D from the control unit.
6. Remove the one  (1) screw holding the air duct to the
oven cavity rear plate.7. Remove the air duct with the air guide cover and the
partition plate from the oven cavity rear plate.
8. Remove the one  (1) screw holding the thermistor angle
to the oven cavity rear plate.
9. Remove the thermistor angle together with thermistor
from the oven.
10.Straighten the tab of the thermistor angle holding the
thermistor to the thermistor angle.
11.Remove the thermistor from the thermistor angle
Removal
1.Disconnect the power supply cord and then remove outer
case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Remove the one (1) screw holding the green wire to the
cavity rear plate.
5. Disconnect the leads of the power supply cord from the
main wire harness.
6. Release the power supply cord from the oven cavity rear
plate.
7. Now, the power supply cord is free.
Re-install
1. Insert the moulding cord stopper of power supply cord
into the square hole of the oven cavity rear plate,
referring to the Figure C-3.
2. Install the earth wire lead of power supply cord to the
POWER SUPPLY CORD REPLACEMENT
Figure C-3. Power Supply Cord Replacement
Power
Supply Cord Moulding
Cord Stopper
Oven Cavity
Rear Plate
Square Hole
cavity rear plate with one (1) screw and tighten the screw.
3. Connect the brown and blue wire leads of power supply
cord to the main wire harness correctly, referring to the
Pictorial Diagram.
1. Disconnect the power supply cord and then remove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Remove the one (1) screw holding the exhaust duct to
the oven cavity.
5. Remove the exhaust duct from the oven cavity.
6. Disconnect the wire leads from the grill heaters.
7. Lay down the two (2) tabs holding the reflector to the
GRIL HEATER (TOP HEATER) REMOVAL
oven cavity.
8. Remove the reflector from the oven cavity by sliding it
leftward.
9. Remove the grill heaters and the short terminal together
from the oven cavity top plate.
10.Remove the two (2) screws holding the short terminal to
the grill heaters.
11.Now the individual grill heaters are free.
1. Disconnect the power supply cord and then remove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Remove the fan duct from the oven cavity, referring to
FAN MOTOR REPLACEMENT.
5. Disconnect the wire leads from the bottom heater.
BOTTOM HEATER REMOVAL
6. Remove the two (2) nuts holding the bottom heater with
the bottom heater angle and the heat seal spring to the
oven cavity right wall.
7. Remove the two (2) nuts holding the bottom heater with
the bottom heater angle and the heat seal spring to the
oven cavity left wall.
8. Remove the bottom heater from the oven cavity .
1. Disconnect the power supply cord and then remove
outer case.2. Open the door and block it open.
3. Discharge high voltage capacitor.
THERMISTOR REMOVAL 
						

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R-820BW
REMOVAL
1. Disconnect the power supply cord.
2. Push the open button and open the door slightly.
3. Insert a putty knife (thickness of about 0.5mm) into the
gap between the choke cover and door frame as shown
in Figure C-6 to free engaging parts.
4. Pry the principles of the lever and lift up the choke cover
by inserting a putty knife as shown in Figure C-6.
5. Release choke cover  from door panel.
6. Now choke cover is free.
DOOR REPLACEMENT
DOOR SENSING SWITCH/SECONDARY INTERLOCK SWITCH AND MONITOR SWITCH ADJUSTMENT
1. Disconnect the power supply cord and then remove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
If the door sensing switch, secondary interlock switch and
monitor switch do not operate properly due to a
misadjustment, the following adjustment should be made.
4. Loosen the two (2) screws holding latch hook to the oven
cavity front flange.
5. 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 door sensing
switch and secondary interlock switch are activated 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.
6. Secure the screws with washers firmly.
7. Check the operation of all switches. If each switch has
not activated with the door closed, loosen screw and
adjust the latch hook position.
After adjustment, check the following.
1. In and out play of door remains less than 0.5mm when in
the latched position. First check upper position of latchhook, 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. The door sensing switch and secondary interlock switch
interrupt the circuit before the door can be opened.
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 Microwave Measurement Procedure.)
Figure C-5. Latch Switch Adjustments
Figure C-6. Door Disassembly
Putty Knife
Door Frame Choke Cover
TabTab Tab
Secondary
Interlock
Switch Door
Sensing
Switch
Monitor Switch Latch Hook
Latch Hook

Door
Sensing 
Switch
Monitor
Switch
Secondary
Interlock
Switch Switch
Lever Latch
Heads
Door
4. Remove the control panel assembly referring to
CONTROL PANEL ASSEMBLY REMOVAL.
5. Disconnect the leads from all switches.
6. Remove the two (2) screws holding the latch hook to the
oven cavity.
7. Remove the latch hook.
8. Push the retaining tab slightly and remove the switch.
Figure C-4. Switches 
						

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7. Release two (2) pins of door panel from two (2) holes of
upper and lower oven hinges by lifting up.
8. Now, door sub assembly is free from oven cavity.
9. Remove the four (4) screws holding the door panel to the
door frame.
10.Release door panel from seven (7) tabs of door frame by
sliding door panel downward.
11.Now, door panel is free.
12.Slide latch head upward and remove it from door frame
with releasing latch spring from door frame and latch
head.
13.Now, latch head and latch spring are free.
14.Remove the two (2) screws holding the glass stopper to
the door frame.
15.Remove the glass stopper from the door frame.
16.Slide the front door glass left and then slide upwards to
release the tabs holding it.
17.Now, the front door glass is free
RE-INSTALL
1. Re-install the front door glass to the door frame as
follows.
1-1. Insert the lower edge of the front door glass into the six
(6) tabs of the door frame.
1-2. Slide the front door glass upwards and insert the upper
edge of the front door glass into the five (5) tabs of the
door frame.
1-3. Slide the front door glass right and insert the right edge
of the front door glass into the two (2) tabs of the door
frame.
2. Re-install the glass stopper to the door frame as follows.
2-1. Re-install the glass stopper to the door frame so that the
two (2) holes of the glass stopper meet the two (2) pins
of the door frame.
2-2. Hold the glass stopper to the door frame with the two (2)
screws.
3. Re-install the latch spring to the latch head. Re-install the
latch spring to the door frame. Re-install latch head to
door frame.
4. Re-install door panel to door frame by fitting seven (7)
tabs of door frame to seven (7) holes of door panel.
5. Hold the door panel to the door frame with four (4)
screws.
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;
(A) Make sure that door sensing switch and secondary
interlock switch are operating properly. (Refer to
chapter Test Procedures.).
(B) An approved microwave survey meter should be
used to assure compliance with proper microwave
radiation emission limitation standards. (Refer to
Microwave Measurement Procedure.)
After any service, make sure of the following :
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
Upper Oven
Hinge Upper 
Oven
Hinge
Lower 
Oven
HingeLower 
Oven
Hinge
Pin
Pin
Choke Cover Door
Panel
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 microwave survey meter.  (Refer to Microwave
Measurement Procedure.)
Note: The door on a microwave oven is designed to act as
an electronic seal preventing the leakage of microwave
energy from oven cavity during cook cycle. This
function does not require that door be air-tight,
moisture (condensation)-tight or light-tight. Therefore,
occasional appearance of moisture, light or sensing
of gentle warm air movement around oven door is not
abnormal and do not in themselves indicate a leakage
of microwave energy from oven cavity.
Figure C-7. Door Replacement 
						

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6
45
12
3
6
45
12
3 A
B
C
D
E
F
G
HA
B
C
D
E
F
G
H
Figure S-2. Power Unit Circuit
+
–
+
–+
–
COM
N.O.
COM
N.O.
COM
N.O.
COM
N.O.
A 3
OVEN LAMP
TURNTABLE
MOTOR

BOTTOM
HEATER
TOP
HEATER
MICRO
DOOR SWITCH
OVEN THERMISTOR AC120V
60HzLED
GND
VC
VA
VR
INT
BUZZER
FAN MOTOR
CONVECTION
MOTOR
N.C.
OVEN
THERMISTOR
N.C. MICRO OVEN LAMP
TURNTABLE
MOTOR
BOTTOM
HEATER
TOP
HEATER
DOOR
SWITCH FAN MOTOR
CONVECTION
MOTOR
Q2  2SB1238
R4  27
R5  4.7k
R3  510 1/2w
R2  510 1/2w
RY5
RY6
RY4Q3
DTD143ES
C5
10µ/35v
RY3
RY2R6  3.3kSP1 D5
D1 D1-4
11ES1 T1
D2
D4
cd
abD3 4
6
18
VRS1
(J1)
C1  0.1µ/50v
C3  0.1µ/50v D12 D11

RY1
D7 D10 D9 D8
C4  10µ/35v C2  470µ/50v10G471K
D6
A 1
B 2B 1D 3D 1
C12
C13
C17
C 7
C11
C 8
C14
C 6
C16
C15
C 5
C 4
C 9
C 1
C 3
C 2
C10
NOTE : IF NOT SPECIFIED,  1/4w ± 5%
: IF NOT SPECIFIED,  1SS270A
A 5