Sharp R1481 Manual

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TEST PROCEDURES
PROCEDURE
LETTERCOMPONENT TEST
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 transformer.
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.
7. Remove the outer case and check voltage between Pin No. 7 of the 4 pin connector (A) and the
common terminal of the relay RY1 on the control unit with an A.C. voltmeter.
The meter should indicate 120 volts, if not check oven circuit.
RY1 and RY2 Relay Test
These relays are operated by D.C. voltage
Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking operation.
DC. voltage indicated ................... Defective relay.
DC. voltage not indicated ............. Check diode which is connected to the relay coil. If diode is
good, control unit is defective.
RELAY SYMBOL OPERATIONAL VOLTAGE CONNECTED COMPONENTS
RY1 Approx. 24.0V D.C. Oven lamp / Fan motor / Stirrer motor
RY2(COOK) Approx. 24.0V D.C. Power transformer
RY3 Approx. 24.0V D.C. Turntable motor
RY4 Approx. 24.0V D.C. Hood motor
RY5 Approx. 24.0V D.C. Hood motor (HIGH /LOW selection)
  8.Disconnect the power supply cord, and then remove outer case.
  9.Open the door and block it open.
10.Discharge high voltage capacitor.
11.Reconnect all leads removed from components during testing.
12.Re-install the outer case (cabinet).
13.Reconnect the power supply cord after the outer case is installed.
14.Run the oven and check all functions.
NRELAY TEST
OCOMPU DEFROST TEST
(1) Place one cup of water in the center of the turntable tray in the oven cavity.
(2) Close the door, touch the  COMPU DEFROST  pad once and touch the Number pad 1 and touch
the Number pad 5. And then touch the START pad.
(3) The oven is in Compu Defrost cooking condition.
(4) The oven will operate as follows
WEIGHT 1ST STAGE 2ND STAGE 3RD STAGE 4TH STAGE
LEVEL TIME LEVEL TIME LEVEL TIME LEVEL TIME
0.5lbs 70% 35sec. 0% 40sec. 50% 30sec. 30% 35sec.
(5) If improper operation is indicated, the control unit is probably defective and should be checked.
To protect the electronic circuits, this model is provided with a fine foil pattern added to the primary on
the PWB, this foil pattern acts as a fuse.
1. Foil pattern check and repairs.
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) Follow the troubleshooting guide given below for repair.
PFOIL PATTERN ON THE PRINTED WIRING BOARD TEST 
						

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TEST PROCEDURES
PROCEDURE
LETTERCOMPONENT TEST
STEPS OCCURRENCE CAUSE OR CORRECTION
1 Only pattern at a is broken. *Insert jumper wire J1 and solder.
2 Pattern at a and b are broken. *Insert the coil RCILF2003YAZZ between c and d.
5) Make a visual inspection of the varistor.
Check for burned damage and examine
the transformer with a tester for the
presence of layer short-circuit (check
the primary coil resistance which is
approximately 192W ± 15%). If any
abnormal condition is detected, replace
the defective parts.
6) Reconnect all leads removed from components during testing.
7) Re-install the outer case (cabinet).
8) Reconnect the power supply cord after the outer case is installed.
9) Run the oven and check all functions.
2. Follow the troubleshooting guide given below, if indicator does not light up after above check and
repairs are finished.
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 transformer.
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.
7) Follow the troubleshooting guide given below for repair.
STEPS OCCURRENCE CAUSE OR CORRECTION
The rated AC voltage is not present between
1 Pin No. 7 of the 4-pin connector (A) and the Check supply voltage and oven power cord.
common terminal of the relay RY1.
2The rated AC voltage is present at primary Low voltage transformer or secondary circuit defective.
side of low voltage transformer. Check and repair.
8) Disconnect the power supply cord, and then remove outer case.
9) Open the door and block it open.
10) Discharge high voltage capacitor.
11) Reconnect all leads removed from components during testing.
12) Re-install the outer case (cabinet).
13) Reconnect the power supply cord after the outer case is installed.
14) Run the oven and check all functions.
D20T1
a b
cd
(470V)
VRS1
CN-A
AC(N) TTM RY3AC(H)
B 1
3 5 7
11 7
2C100
(J1) 
Q27  
						

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TOUCH CONTROL PANEL ASSEMBLY
OUTLINE OF TOUCH CONTROL PANEL
3) Synchronizing Signal Circuit
The power source synchronizing signal is available in
order to compose a basic standard time in the clock
circuit. It incorporates a very small error because it works
on commercial frequency.
4) ACL Circuit
A circuit to generate a signals which resetting the LSI to
the initial state when power is applied.
5) Buzzer Circuit
The buzzer responds to signals from the LSI to emit
audible sounds (key touch sound and completion sound).
6) Door Sensing Switch
A switch to inform the LSI if the door is open or closed.
7) Relay Circuit
To drive the magnetron, fan motor, stirrer motor, turnta-
ble motor, hood motor, and light the oven lamp and hood
lamp.
8) Indicator Circuit
Indicator element is a Fluorescent Display.
Basically, a Fluorescent Display is a triode having a
cathode, a grid and an anode. Usually, the cathode of a
Fluorescent Display is directly heated and the filament
serves as cathode.
The Fluorescent Display has 8-digits, 15-segments are
used for displaying figures.
The touch control section consists of the following units
as shown in the touch control panel circuit.
(1) Key Unit
(2) Control Unit
The principal functions of these units and the signals com-
municated among them are explained below.
Key Unit
The key unit is composed of a matrix, signals generated in
the LSI are sent to the key unit through P00 - P07.
When a key pad is touched, a signal is completed through
the key unit and passed back to the LSI through R24 - R27
to perform the function that was requested.
Control Unit
Control unit consists of LSI, power source circuit, synchro-
nizing signal circuit, ACL circuit, buzzer circuit, relay circuit
and indicator circuit.
1) LSI
This LSI controls the key strobe signal, relay driving
signal for oven function and indicator signal.
2) Power Source Circuit
This circuit generates voltages necessary for the control
unit from the AC line voltage.
Symbol Voltage Application
VC -5.1V LSI(IC1)
VP -28V Fluorescent display tube : Grid
and anode voltage
VF1-VF2 2.7Vac Filament of fluorescent dis-
play tube
(VF1 to VF2 voltage) 
						

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DESCRIPTION OF LSI
LSI(IZA876DR)
The I/O signals of the LSI(IZA876DR) are detailed in the following table.
Pin No. Signal I/O Description
1 VCC IN Connected to GND.
2 VEE IN
Anode (segment) of Fluorescent Display illumination voltage: -31V.
Vp voltage of power source circuit input.
3 AVSS IN
Power source voltage:-5V.
VC voltage of power source circuit input.
4 VREF IN
Reference voltage input terminal.
A reference voltage applied to the A/D converter in the LSI. Connected to GND.(0V)
5-6 AN7-AN6 IN Terminal not used.
7-9 AN5-AN3 INHeating constant compensation terminal.
10 AN2 IN
Input signal which communicates the door open/close information to LSI.
Door closed; L level signal(0V).
Door opened; H level signal(-5V).
11-12 AN1-AN0 IN Connected to GND(0V).
13 P55 OUT Terminal not used.
14 P54 OUT
Oven lamp, Stirrer motor and Fan motor driving signal. (Square Waveform : 60Hz)
To turn on and off the shut-off relay(RY1). The
square waveform voltage is delivered to the
relay(RY1) driving circuit.
15 P53 OUTTurntable motor driving signal.
To turn on and off relay(RY3). L level: During
Turntable ON. H level: During Turntable OFF or
during the oven is off condition.
16 P52 OUT Terminal not used.
17 P51 OUTMagnetron high-voltage circuit driving signal.
To turn on and off the cook
relay(RY2). In P-HI operation, the
signals holds L level during mi-
crowave cooking and  H level
while not cooking. In other cook-
ing modes (P-90,P-80,P-70,P-
60,P-50,P-40,P-30,P-20,P-10,P-
0) the signal turns to  H level and
L level in  repetition according to
the power level.
18 P50 OUT Terminal not used.
19 P47 OUT
Hood lamp driving signal.
To turn on and off solid state relay(SSR1). 1
level: During Hood lamp ON (WORK LIGHT level).
2 level: During Hood lamp ON (NIGHT LIGHT
level).  H level: During Hood lamp OFF.
20 P46 OUTHood motor driving signal.
To turn on and off relay(RY9). L level: During Hood
motor ON. H level: During Hood motor OFF.
21 P45 OUT
Hood motor high / low driving signal.
To turn on and off relay(RY5). L level: During Hood
motor high. H level: During Hood motor low.
ONOFF
H : GND
L
During cookingL
H16.7 msec.
VARI-MODE ON TIME OFF TIME
P-HI (100% power) 32 sec. 0 sec.
P-90 (approx. 90% power) 30 sec. 2 sec.
P-80 (approx. 80% power) 26 sec. 6 sec.
P-70 (approx. 70% power) 24 sec. 8 sec.
P-60 (approx. 60% power) 22 sec. 10 sec.
P-50 (approx. 50% power) 18 sec. 14 sec.
P-40 (approx. 40% power) 16 sec. 16 sec.
P-30 (approx. 30% power) 12 sec. 20 sec.
P-20 (approx. 20% power) 8 sec. 24 sec.
P-10 (approx. 10% power) 6 sec. 26 sec.
P-0 (0% power) 0 sec. 32 sec.
L 1H
LAC
CURRENT
WORK
LIGHT
NIGHT
LIGHT H
2
ONOFF
H : GND
L ONOFF
H : GND
L 
						

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22 P44 OUT Terminal not used.
23 P43 OUT
Signal to sound buzzer.
A: key touch sound.
B: Completion sound.
C: When the temperature of the oven cavity reaches
the preset temperature in the preheating mode,
or when the preheating hold time (30 minutes) is
elapsed.
24 P42 IN Terminal not used.
25 INT1 IN
Signal to synchronize LSI with commercial power source frequency.
This is the basic timing for all real time processing of LSI.
26 P40 IN Connected to VC.
27 RESET IN
Auto clear terminal.
Signal is input to reset the LSI to the initial state when power is applied.  Temporarily set
to L level the moment power is applied, at this time the LSI is reset. Thereafter set at H
level.
28-29 P71-P70 OUT Terminal not used.
30 XIN IN
Internal clock oscillation frequency setting input.
The internal clock frequency is set by inserting the ceramic filter oscillation circuit with
respect to XOUT terminal.
31 XOUT OUT
Internal clock oscillation frequency control output.
Output to control oscillation input of XIN.
32 VSS IN
Power source voltage:-5V.
VC voltage of power source circuit input.
33 P27 IN
Signal coming from touch key.
When any one of G12 line keys on key matrix is touched, a corresponding signal will be
input into P27. When no key is touched, the signal is held at L level.
34 P26 IN
Signal similar to P27.
When any one of G11 line keys on key matrix is touched, a corresponding signal will be
input into P26.
35 P25 IN
Signal similar to P27.
When any one of G10 line keys on key matrix is touched, a corresponding signal will be
input into P25.
36 P24 IN
Signal similar to P27.
When any one of G9 line keys on key matrix is touched, a corresponding signal will be input
into P24.
37-40 P23-P20 OUT
Digit selection signal.
The relationship between digit signal and digit are as follows;
Digit signal .................................. Digit
P14 ................................................ 1st.
P15 ............................................... 2nd.
P16 ............................................... 3rd.
P17 ................................................ 4th.
P20 ................................................ 5th.
P21 ................................................ 6th.
P22 ................................................ 7th.
P23 ................................................ 8th.
(§ : INTO signal)
Refer to the touch control panel circuit about the
relation between signals and digits.  Normally,
one pulse is output in every synchronized signal
(§) period, and input to the grid of the fluorescent
display.
Pin No. Signal I/O Description
A
B
C
H: GND
L 0.1 sec
2 sec
1 sec
1 sec
H : GND
L (-5V)
16.7 msec
H
L
GND
VP ß(60Hz)
P14
P15
P16
P17
P20
P21
P22
P23 
						

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Pin No. Signal I/O Description
ß(60Hz)
GND
VP
41-44 P17-P14 OUTDigit selection signal.
Signal similar to P23.
45-48 P13-P10 OUT
Segment data signals.
The relation between signals and indicators are as follows:
Signal Segment Signal Segment
P13 ............... P15 P03 ................ P7
P12 ............... P14 P02 ................ P6
P11 ............... P13 P01 ................ P5
P10 ............... P12 P00 ................ P4
P07 ............... P11 P37 ................ P3
P06 ............... P10 P36 ................ P2
P05 ................. P9 P35 ................ P1
P04 ................. P8
(§ : INTO signal)
Refer to the touch control panel circuit about the relation between signals and indicators.
Normally, one pulse is output in every synchronized signal (§) period, and input to the
anode of the fluorescent display.
49 P07 OUTSegment data signal.Signal similar to P13.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P27 - P24 terminal  while one
of G8 line keys on key matrix is touched.
50 P06 OUTSegment data signal.Signal similar to P13.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P27 - P24 terminal  while one
of G7 line keys on key matrix is touched.
51 P05 OUTSegment data signal.Signal similar to P13.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P27 - P24 terminal  while one
of G6 line keys on key matrix is touched.
52 P04 OUTSegment data signal.Signal similar to P13.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P27 - P24 terminal  while one
of G5 line keys on key matrix is touched.
53 P04 OUTSegment data signal.Signal similar to P13.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P27 - P24 terminal  while one
of G4 line keys on key matrix is touched.
54 P02 OUTSegment data signal.Signal similar to P13.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P27 - P24 terminal  while one
of G3 line keys on key matrix is touched.
55 P01 OUTSegment data signal.Signal similar to P13.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P27 - P24 terminal  while one
of G2 line keys on key matrix is touched.
56 P00 OUT
Segment data signal.
Signal similar to P13.
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P27 - P24 terminal  while one
of G1 line keys on key matrix is touched.
57-59 P37-P35 OUTSegment data signal.Signal similar to P13.
60-64 P34-P30 OUT Terminal not used. 
						

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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 all 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.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, 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 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.
SERVICING
approx. 1M ohm
ECBTransistor
DTA123ES
KRA101M
KRC243M
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 MI-
CROWAVE OVEN IS STILL LIVE DURING SERVICING
AND PRESENTS A HAZARD.
Therefore, 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
transformer.
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
transformer.
4) Re-install the outer case (cabinet). 
						

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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:
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 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
and Oven cavity.
WARNING FOR WIRING
1. Disconnect the power supply cord.
2. 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 PANAL PARTS, DOOR PARTSÕ, when carrying out any of
the following removal procedures:
THE FOLLOWING ADJUSTMENTS OR COMPONENT REPLACEMENT CAN BE PERFORMED
WITHOUT REMOVING THE OVEN FROM THE WALL
1. Hood lamps, sockets and grease filter.
2. Oven lamp, base cover and hood lamp glass assembly.
3. Turntable motor.4. Hood exhaust louver.
5. Control panel assembly or components
6. Stirrer cover and stirrer fan.
 HOOD EXHAUST LOUVER REMOVAL
1. Disconnect the power supply cord.
2. Open the door and block it open.
3. Remove the one (1) screw holding the hood exhaust
louver to the oven cavity with the outer case cabinet.
Hood exhaust 
louver
Tab (left )
Tab (right) 
Push 
Push  
						

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REMOVAL OF OVEN FROM WALL (Two persons recommended to remove the oven)
1. Disconnect the power supply cord, and uncoil the power
supply cord.
2. Remove the turntable tray and support from the oven cavity.
3. Remove the one (1) screw holding the exhaust  damper
assembly to the rear stay, and remove the exhaust
damper assembly by sliding it backward.
4. Remove the two (2) screws holding the oven (outer case
cabinet) to the top cabinet.
5. Remove the hood exhaust louver referring to HOOD
EXHAUST LOUVER REMOVAL.6. While supporting the front of the oven, unfasten the two
(2) unit mounting screws holding the oven to the unit
mounting plate.
7. Remove the oven by sliding it into the arms of the unit
mounting plate and pull the power cord out of the wall
cabinet.
8. The oven is now free and can be placed on the work
surface selected for servicing the oven.
9. Installation is the reverse of this procedure.
OUTER CASE REMOVAL
Remove the oven from the wall and proceed as follows;
1. Disconnect the power supply cord.
2. Open the door and block it open.
3. Remove one (1) screw holding the hood exhaust louver
to the oven, and pull it forward to remove by pushing the
right and left tabs of the hood exhaust louver. (Refer to
procedure of  HOOD EXHAUST LOUVER REMOVAL.)
4. Remove four (4) screws holding the rear stay to the hood
fan motor or the oven, and remove it.
5. Remove the four (4) screws from the rear of the outer
case cabinet.
6. Slide the outer case cabinet back about 1 inch (3 cm) tofree it from retaining clips on the cavity face plate.
7. Disconnect the three (3) pin connector of the power
supply cord from the wiring harness and remove the
power supply cord together with the outer case.
8. Discharge high voltage capacitor.
CAUTION: 1.DISCONNECT OVEN FROM POWER
SUPPLY BEFORE REMOVING OUTER
CASE.
2. DISCHARGE THE HIGH VOLTAGE
CAPACITOR BEFORE TOUCHING ANY
OVEN COMPONENTS OR WIRING.
POWER TRANSFORMER REMOVAL
1. Disconnect the power supply cord, remove the oven
from wall, and remove outer case. (Refer to procedure of
Removal of Oven from Wall and  Outer Case Removal.)
And proceed as follows.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Remove one (1) screw holding the hood duct to the oven
cavity front flange.
5.
Disconnect the stop switch harness from the chassis
support and disconnect the wire leads from the fan motor.
6. Lift up the fan motor side of the hood duct.
7. Disconnect filament leads of transformer from the
magnetron and capacitor.
8. Disconnect high voltage leads of capacitor from the
transformer.
9. Disconnect wire leads from transformer.
10.Remove two (2) screws holding the transformer to right
base plate.Re-install
1. Install by sliding the transformer on the right base plate
with its primary terminals toward the outer case.
2. Secure the transformer with two (2) screws to right base
plate.
3. Re-connect wire leads (primary and high voltage) to the
transformer and filament leads of transformer to
magnetron and high voltage capacitor. Refer to
PICTORIAL DIAGRAM.
4. Re-install the hood duct holding the fan motor to the oven
cavity front flange with one (1) screw.
5. Reconnect the wire leads to the chassis support and the
fan motor, referring to PICTORIAL DIAGRAM.
6. Re-install the outer case and check that oven is operating
properly.
CAUTION:MAKE SURE THE WIRE LEADS NEVER
TOUCH THE FAN BLADE. 4. Pull the hood exhaust louver from the oven cavity by
pushing the right and left tabs of the hood exhaust louverto remove.
5. Now, the hood exhaust louver is free.
HOOD FAN MOTOR, HOOD DUCT AND OVEN LAMP SOCKET REMOVAL
1. Disconnect the power supply cord and remove the oven
from wall and remove outer case. (Refer to procedure of
Removal of Oven from Wall and Outer case Removal)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect the 6-pin connector of the hood fan motor
from the main wire harness located at the right edge of
the hood duct and release the snap band from the hood
duct.5. Remove the hood fan motor  from the hood duct by lifting
it up.
6. Now, the hood fan motor is free.
7. Remove  one (1) screw holding the hood duct to the oven
cavity front plate.
8. Release the 6-pin connector and the 3-pin connector of
the main harness A from the hood duct.
9. Disconnect the wire leads from the fan motor and chassis
support, and release the wire leads from holes of the 
						

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R-1480
R-1481
R-1482
hood duct.
10.Remove the two (2) unit mounting screws from the
chassis support (right side) and the hood duct (left side).
11.Remove the one (1) screw holding the chassis support.
12.Remove the chassis support.
13.Remove the hood duct from the oven cavity by lifting it up
14.Screw the oven lamp off from the lamp socket.
15.Remove the lamp socket from the lamp angle.
16.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.17.Now, the oven lamp socket and the hood duct are free.
1. Disconnect the power supply cord , remove the oven
from wall and remove outer case (Refer to procedure of
Removal of Oven from Wall and Outer case Removal.)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect  the wire leads from the fan motor and the
chassis support, and release them from the holes of
hood duct.
5. Remove the one (1) screw holding the hood duct to the
oven cavity front plate, and lift up the fan motor side of the
hood duct.
6. Remove the one (1) screw holding the capacitor holder to
the hood intake duct.
7. Disconnect  the high voltage wire leads of the high
voltage rectifier assembly from the magnetron.
MAGNETRON REMOVAL
8. Disconnect the filament lead of the transformer from the
magnetron.
9. Remove the power transformer from the right base plate,
referring to POWER TRANSFORMER REMOVAL.
10.Carefully remove four (4) mounting screws holding the
magnetron to waveguide. When removing the screws
hold the magnetron to prevent it from falling.
11.Remove the magnetron from the unit with care so the
magnetron tube should not be hit by any metal object
around the tube.
CAUTION: WHEN REPLACING THE MAGNETRON, BE
SURE THE R.F. GASKET IS IN PLACE AND
MOUNTING SCREWS ARE TIGHTENED SE-
CURELY.
1. Disconnect the power supply cord , remove the oven
from wall and remove outer case (Refer to procedure of
Removal of Oven from Wall and Outer case Removal.)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect  the wire leads from the fan motor and the
chassis support, and release them from the holes of
hood duct.
5. Remove the one (1) screw holding the hood duct to the
oven cavity front flange, and lift up the fan motor side of
the hood duct.
6. Disconnect the high voltage wire leads with high voltage
rectifier from the magnetron.
7. Disconnect filament lead of the transformer from high
HIGH VOLTAGE RECTIFIER AND HIGH VOLTAGE CAPACITOR REMOVAL
voltage capacitor.
8. Disconnect high voltage wire from capacitor.
9. Remove  one (1) screw holding capacitor holder and high
voltage rectifier to the hood intake duct.
10.Disconnect the high voltage rectifier assembly from the
high voltage capacitor.
11.Now, the high voltage rectifier assembly is free.
12.Remove capacitor from the holder.
13.Now, the high voltage capacitor is free.
CAUTION: WHEN REPLACING THE HIGH VOLTAGE
RECTIFIER ASSEMBLY, THE GROUND SIDE
TERMINAL MUST BE SECURED FIRMLY
WITH A GROUNDING SCREW.
THERMAL CUT-OUT (CAVITY) REMOVAL
Oven lamp
socket
Terminal
Wire lead
Terminal hole
Flate type small
screw driver
1. Disconnect the power supply cord and remove the oven
from wall and remove outer case. (Refer to procedure of
Removal of Oven from Wall and Outer case Removal)
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect the wire leads from the hood fan thermal
HOOD FAN THERMAL CUT-OUT REMOVAL
cut-out.
5. Remove one (1) screw holding the thermal cut-out to the
right base plate.
6. Remove the hood fan thermal cut-out from the  right base
plate.
7. Now, the hood fan thermal cut-out is free.
1. Disconnect the power supply cord and remove the oven
from wall and remove outer case. (Refer to procedure ofRemoval of Oven from Wall and Outer case Removal)
2. Open the door and block it open.