Sharp Carousel R-1510 User manual

31
R-1510
R-1511
In the interest of user-safety the oven should be restored to its
originalconditionandonlypartsidenticaltothosespecifiedshould
be used.
WARNING TO SERVICE PERSONNEL: Microwave ovens con-
tain circuitry capable of producing very high voltage and
current. Contact with the following parts may result in a
severe, possibly fatal, electrical shock. (High Voltage Capaci-
tor, High Voltage Power Transformer, Magnetron, High Volt-
age Rectifier Assembly, High Voltage Harness etc..)
TABLE OF CONTENTS Page
PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO
AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY ...................INSIDE FRONT COVER
BEFORE SERVICING ......................................................................................................INSIDE FRONT COVER
WARNING TO SERVICE PERSONNEL................................................................................................................1
MICROWAVE MEASUREMENT PROCEDURE ...................................................................................................2
FOREWORD AND WARNING...............................................................................................................................3
PRODUCT SPECIFICATIONS ..............................................................................................................................4
CONTROL PANEL.................................................................................................................................................5
OPERATION..........................................................................................................................................................5
TROUBLESHOOTING GUIDE ..............................................................................................................................7
TEST PROCEDURE ..............................................................................................................................................8
TOUCH CONTROL PANEL ASSEMBLY ............................................................................................................14
COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE ................................................................19
PICTORIAL DIAGRAM ........................................................................................................................................22
POWER UNIT CIRCUIT ......................................................................................................................................23
LSI UNIT CIRCUIT...............................................................................................................................................24
PRINTED WIRING BOARD .................................................................................................................................25
PARTS LIST ........................................................................................................................................................26
PACKING AND ACCESSORIES .........................................................................................................................28
S2205R1510X//
R-1510
R-1511
OVER THE RANGE
MICROWAVE OVEN
MODELS
SERVICE MANUAL
SHARP CORPORATION This document has been published to be used for after
sales service only.
The contents are subject to change without notice.
SENSOR
ThisisasupplementalServiceManualforModelsR-1510andR-1511.Thesemodelsarequitesimilartobasemodel
R-1500 and R-1501. Use this supplemental manual together with the Base Models Service Manual (Reference No.
is S8123R1500X//) for complete operation, service information, etc..

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R-1510
R-1511
PRECAUTIONS TO BE OBSERVED BEFORE AND
DURING SERVICING TO AVOID POSSIBLE EXPO-
SURE TO EXCESSIVE MICROWAVE ENERGY
(a) Do not operate or allow the oven to be operated with the door open.
(b) Make the following safety checks on all ovens to be serviced before activating the magnetron or other
microwavesource,andmakerepairsasnecessary:(1)interlockoperation,(2)properdoorclosing,(3)seal
andsealingsurfaces(arcing,wear,andotherdamage), (4)damagetoorloosening ofhingesandlatches,
(5) evidence of dropping or abuse.
(c) Before turning on microwave power for any service test or inspection within the microwave generating
compartments, check the magnetron, wave guide or transmission line, and cavity for proper alignment,
integrity, and connections.
(d) Any defective or misadjusted components in the interlock, monitor, door seal, and microwave generation
andtransmissionsystemsshallberepaired,replaced,oradjustedbyproceduresdescribedinthismanual
before the oven is released to the owner.
(e) A microwave leakage check to verify compliance with the Federal Performance Standard should be
performed on each oven prior to release to the owner.
BEFORE SERVICING
Before servicing an operative unit, perform a microwave emission check as per the Microwave
Measurement Procedure outlined in this service manual.
If microwave emissions level is in excess of the specified limit, contact SHARP ELECTRONICS
CORPORATION immediately @1-800-237-4277.
If the unit operates with the door open, service person should 1) tell the user not to operate the oven
and 2) contact SHARP ELECTRONICS CORPORATION and Food and Drug Administration's
Center for Devices and Radiological Health immediately.
Service personnel should inform SHARP ELECTRONICS CORPORATION of any certified unit
found with emissions in excess of 4mW/cm2. The owner of the unit should be instructed not to use
the unit until the oven has been brought into compliance.

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R-1511
WARNING TO SERVICE PERSONNEL
Microwave ovens contain circuitry capable of pro-
ducing very high voltage and current, contact with
following parts
may result in a severe, possibly
fatal, electrical shock.
(Example)
HighVoltageCapacitor,HighVoltagePowerTrans-
former,Magnetron,HighVoltageRectifierAssem-
bly, High Voltage Harness etc..
Read the Service Manual carefully and follow all
instructions.
Before Servicing
1. Disconnectthepowersupplycord ,andthenremove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
WARNING:RISK OF ELECTRIC SHOCK.
DISCHARGE THE HIGH-VOLTAGE
CAPACITOR BEFORE SERVICING.
The high-voltage capacitor remains charged about 60
secondsaftertheovenhasbeenswitchedoff.Waitfor60
secondsandthenshort-circuittheconnectionofthehigh-
voltagecapacitor (thatis theconnectinglead ofthe high-
voltage rectifier) against the chassis with the use of an
insulated screwdriver.
Whenever troubleshooting is performed the power supply
mustbedisconnected.Itmay,insomecases,benecessary
to connect the power supply after the outer case has been
removed, in this event,
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, reconnect the power supply cord.
When the testing is completed,
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. Reconnect the leads to the primary of the power
transformer.
5. Reinstall the outer case (cabinet).
6. Reconnectthepowersupplycord afterthe outercase is
installed.
7. Run the oven and check all functions.
After repairing
1. Reconnect all leads removed from components during
testing.
2. Reinstall the outer case (cabinet).
3. Reconnectthepowersupplycord afterthe outercase is
installed.
4. Run the oven and check all functions.
Microwave ovens should not be run empty. To test for the
presence of microwave energy within a cavity, place a cup
of cold water on the oven turntable, close the door and set
the power to HIGH and set the microwave timer for two (2)
minutes.Whenthe twominutes haselapsed(timer atzero)
carefully check that the water is now hot. If the water
remainscoldcarryout BeforeServicingprocedureandre-
examine the connections to the component being tested.
When all service work is completed and the oven is fully
assembled,themicrowavepoweroutputshouldbechecked
and microwave leakage test should be carried out.
Don't Touch !
Danger High Voltage

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MICROWAVE MEASUREMENT PROCEDURE
A. Requirements:
1) Microwave leakage limit (Power density limit): The power density of microwave radiation emitted by a microwave oven
shouldnotexceed1mW/cm2atanypoint5cmormorefromtheexternalsurfaceoftheoven,measuredpriortoacquisition
bya purchaser,andthereafter (throughtheuseful lifeoftheoven), 5mW/cm2atanypoint 5cmormorefrom theexternal
surface of the oven.
2) Safety interlock switches: Primary interlock switch shall prevent microwave radiation emission in excess of the
requirement as above mentioned, secondary interlock relay and door sensing switch shall prevent microwave radiation
emission in excess of 5 mW/cm2at any point 5cm or more from the external surface of the oven.
B. Preparation for testing:
Before beginning the actual measurement of leakage, proceed as follows:
1) Make sure that the actual instrument is operating normally as specified in its instruction booklet.
Important:
Surveyinstruments thatcomply withtherequirementforinstrumentationasprescribedbytheperformancestandard
for microwave ovens, 21 CFR 1030.10(c)(3)(i), must be used for testing.
2) Place the oven tray in the oven cavity.
3) Place the load of 275±15 ml (9.8 oz) of tap water initially at 20±5˚C (68˚F) in the center of the oven cavity.
The water container shall be a low form of 600 ml (20 oz) beaker with an inside diameter of approx. 8.5 cm (3-1/2 in.)
and made of an electrically nonconductive material such as glass or plastic.
Theplacingof thisstandard loadin theoven isimportantnot onlyto protectthe oven,but alsotoinsure thatany leakage
is measured accurately.
4) Set the cooking control on Full Power Cooking Mode
5) Close the door and select a cook cycle of several minutes. If the water begins to boil before the survey is completed,
replace it with 275 ml of cool water.
C. Leakage test:
Closed-door leakage test (microwave measurement)
1) Grasptheprobeofthesurveyinstrumentandholditperpendiculartothegapbetweenthedoorandthebodyoftheoven.
2) Move the probe slowly, not faster than 1 in./sec. (2.5 cm/sec.) along the gap, watching for the maximum indication on
the meter.
3) Checkforleakageatthedoorscreen,sheetmetalseamsandotheraccessiblepositionswherethecontinuityofthemetal
has been breached (eg., around the switches, indicator, and vents).
Whiletestingforleakagearoundthedoorpullthedoorawayfromthefrontoftheovenasfarasispermittedbytheclosed
latch assembly.
4) Measure carefully at the point of highest leakage and make sure that the highest leakage is no greater than 4mW/cm2,
andthattheprimaryinterlockswitchandthesecondaryinterlock relaydo turnthe ovenOFF beforeanydoormovement.
NOTE: After servicing, record data on service invoice and microwave leakage report.

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R-1511
SHARP ELECTRONICS CORPORATION
SHARP PLAZA, MAHWAH,
NEW JERSEY 07430-2135
SERVICE MANUAL
OVER THE RANGE
MICROWAVE OVEN
R-1510/ R-1511
FOREWORD
This Manual has been prepared to provide Sharp Electronics Corp. Service Personnel with Operation and Service
Information for the SHARP OVER THE RANGE MICROWAVE OVEN, R-1510 and R-1511.
The models R-1510 and R-1511 are quite similar to base models R-1500 and R-1501 (Reference No. is S8123R1500X//).
It is recommended that service personnel carefully study the entire text of this manual and base model service manual so
that they will be qualified to render satisfactory customer service.
Check the interlock switches and the door seal carefully. Special attention should be given to avoid electrical shock and
microwave radiation hazard.
WARNING
Never operate the oven until the following points are ensured.
(A) The door is tightly closed.
(B) The door brackets and hinges are not defective.
(C) The door packing is not damaged.
(D) The door is not deformed or warped.
(E) There is not any other visible damage with the oven.
Servicing and repair work must be carried out only by trained service personnel.
DANGER
Certain initial parts are intentionally not grounded and present a risk of electrical shock only during servicing.
Service personnel - Do not contact the following parts while the appliance is energized;
High Voltage Capacitor, Power Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage
Harness;
If provided, Vent Hood, Fan assembly, Cooling Fan Motor.
All the parts marked “*” on parts list are used at voltages more than 250V.
Removal of the outer wrap gives access to voltage above 250V.
Allthepartsmarked“∆”onpartslistmaycauseunduemicrowaveexposure,bythemselves,orwhentheyaredamaged,
loosened or removed.

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R-1511
ITEM DESCRIPTION
Power Requirements 120 Volts / 14 Amperes
60 Hertz
Single phase, 3 wire grounded
Power Output 1000 watts (IEC TEST PROCEDURE)
Operating frequency of 2450MHz
Case Dimensions Width 29-15/16"
Height 16-1/4"
Depth 15- 9/16"
Cooking Cavity Dimensions Width 17-1/2"
Height 9-7/8"
1.5 Cubic Feet Depth 14-15/16"
Hood lamp 2 bulbs, 20W x 2, Incandescent light bulbs
Hood fan Approx. 300 C.F.M.
Control Complement Touch Control System
Clock ( 1:00 - 12:59 )
Timer (0 - 99 min. 99 seconds)
Microwave Power for Variable Cooking
Repetition Rate;
P-HI..................................................Full power throughout the cooking time
P-90 .................................................................... approx. 90% of Full Power
P-80 .................................................................... approx. 80% of Full Power
P-70 .................................................................... approx. 70% of Full Power
P-60 .................................................................... approx. 60% of Full Power
P-50 .................................................................... approx. 50% of Full Power
P-40 .................................................................... approx. 40% of Full Power
P-30 .................................................................... approx. 30% of Full Power
P-20 .................................................................... approx. 20% of Full Power
P-10 .................................................................... approx. 10% of Full Power
P-0 .................................................... No power throughout the cooking time
KEEP WARM PLUS pad,HOT WATER pad, CUSTOM HELP pad
INSTANT SENSOR pads, SENSOR COOK CENTER pads
REHEAT pads, DEFROST CENTER pad, Number selection pads
POWER LEVEL pad, TIMER / CLOCK pad
LIGHT HI / LO button, FAN HI / LO button,
STOP/CLEAR button, START/ MINUTE PLUS button,
Oven Cavity Light 20W x 1 Incandescent light bulb
Safety Standard UL Listed FCC Authorized
DHHS Rules, CFR, Title 21, Chapter 1, Subchapter J
Weight Approx. 55 lbs.
PRODUCT SPECIFICATION

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R-1511
NOTE: Some one-touch cooking features such as "MINUTE
PLUS" are disabled after three minutes when the
oven is not used. These features are automatically
enabled when the door is opened and closed or
STOP/CLEAR button is pressed.
CONTROL PANEL
1000 WATTS
KEEP WARM
PLUS
REHEAT
POWER
LEVEL TIMER
CLOCK
BAKED
POTATOES
POPCORN
FRESH
VEGETABLES
CUSTOM
HELP
HOT
WATER
FRESH ROLLS/
MUFFINS FROZEN ROLLS/ MUFFINS
BEVERAGE
LIGHT HI/ LO
FAN HI/ LO
STOP
CLEAR
START
MINUTE PLUS
INSTANT SENSOR
REHEAT
1 GROUND MEAT
2 RICE
3 FISH/SEAFOOD
4 FROZEN ENTREES
5 CHICKEN BREAST
6 FROZEN VEGETABLES
1 GROUND MEAT
2 STEAKS/CHOPS 3 BONELESS POULTRY 4 BONE-IN POULTRY
06789
51234
COOK SENSOR LBS KG DEF HELP
SENSOR
COOK
CENTER
DEFROST
CENTER
OPERATION
DESCRIPTION OF OPERATING SEQUENCE
Thefollowingisadescriptionofcomponentfunctionsduring
oven operation.
OFF CONDITION
Closing the door activates the door sensing switch and
primary interlock switch. (In this condition, the monitor
switch contacts are opened.)
When oven is plugged in, 120 volts A.C. is supplied to the
control unit. (Figure O-1).
1. The display will show "SHARP SIMPLY THE BEST
PRESS CLEAR AND PRESS CLOCK".
To set any program or set the clock, you must first
touch the STOP/CLEAR button. The display will clear,
and " : " will appear .
POWER LEVEL P-0 TO P-90 COOKING
When Variable Cooking Power is programmed, the 120
voltsA.C.issuppliedtothepowertransformerintermittently
throughthecontactsofrelay(RY2)whichisoperatedbythe
control unit within an interval second time base.
Microwave power operation is as follows:
VARI-MODE ON TIME OFF TIME
HIGH (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.
Note: The ON/OFF time ratio does not correspond with
the percentage of microwave power, because
approx. 3 seconds are needed for heating of the
magnetron filament.

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Figure O-1. Oven Schematic-Off Condition
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. CLOCK APPEARS ON DISPLAY.
SENSOR COOKING CONDITION
Using the Sensor Cooking function, the foods are cooked or
defrostedwithoutfiguringtime,powerlevelorquantity.When
the oven senses enough steam from the food, it relays the
information to its microprocessor which will calculate the
remaining cooking time and power level needed for best
results. When the food is cooked, water vapor is developed.
The sensor “senses” the vapor and its resistance increases
gradually.Whentheresistancereachesthevaluesetaccord-
ing to the menu, supplementary cooking is started. The time
of supplementary cooking is determined by experiment with
each food category and inputted into the LSI.
An example of how sensor works
(Baked potatoes):
1. Potatoes at room temperature.
Vapor is emitted very slowly.
2. Heat potatoes. Moisture
and humidity is emitted
rapidly. You can smell the
aroma as it cooks.
3. Sensor detects moisture and humidity and calculates
cooking time and variable power.
Cooking Sequence.
1. Operatetheoveninsensorcookingmodebyreferringto
operation manual.
NOTE: TheovenshouldnotbeoperatedonSensorCooking
immediately after plugging in the unit. Wait two
minutes before cooking on Sensor Cooking.
2. The coil of shut-off relay (RY1) is energized, the oven
lamp, turntable motor and cooling fan motor are turned
on, but the power transformer is not turned on.
3. Afterabout32seconds,thecookrelay(RY2)isenergized.
The power transformer is turned on, microwave energy
is produced and first stage is started.
The 32 seconds is the cooling time required to remove
any vapor from the oven cavity and sensor.
NOTE: Duringthisfirststage,donotopenthedoorortouch
STOP/CLEAR pad.
4. When the sensor detects the vapor emitted from the
food,thedisplayswitchesoverto theremainingcooking
time and the timer counts down to zero.
At this time, the door may be opened to stir food, turn it
or season, etc.
5. Whenthe timerreaches zero,an audiblesignal sounds.
The shut-off relay and cook relay are de-energized and
the power transformer, oven lamp, etc. are turned off.
6. OpeningthedoorortouchingtheSTOP/CLEARpad,the
timeofdaywillreappearon thedisplay andthe ovenwill
revert to an OFF condition.
MICROWAVE
MICROWAVE
AH SENSOR
NOTE: " " indicates components with potential above 250V.
MAGNETRON
TEMPERATURE FUSE
FUSE
20A
TURNTABLE MOTOR
FAN MOTOR
MAGNETRON
OVEN LAMP
MONITOR SWITCH
BLKWHT
POWER
TRANSFORMER
HIGH VOLTAGE
CAPACITOR
0.94µF/ AC2300V
HIGH VOLTAGE
RECTIFIER
COM.
N.O.
COM.
CONTROL UNIT
GND
GRN
HOOD
MOTOR
A5
B5
B7
B9 Low
High
A1 A3 B1 B3 N.O.
E1
E2
DOOR
SENSING
SWITCH
PRIMARY
INTERLOCK
SWITCH
120 V AC.
60 Hz
HOOD
LAMP
HL
RY1
RY2
SECONDARY
INTERLOCK
RELAY
OVEN LAMP
RELAY
FM
OL
TTM
HOOD FAN
THERMAL
CUT OUT
HOOD
CAPACITOR
RY4
RY6
RY5
RY3
N.C.
CAVITY
THERMAL CUT-OUT
HL
F1
F2
F3
AH SENSOR

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SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. COOKING TIME PROGRAMMED.
3. VARIABLECOOKINGCONTROL"HIGH".
4. "START" BUTTON PRESSED.
Figure O-2. Oven Schematic-Cooking Condition
MAGNETRON
TEMPERATURE FUSE
FUSE
20A
TURNTABLE MOTOR
FAN MOTOR
MAGNETRON
OVEN LAMP
MONITOR SWITCH
BLKWHT
POWER
TRANSFORMER
HIGH VOLTAGE
CAPACITOR
0.94µF/ AC2300V
HIGH VOLTAGE
RECTIFIER
COM.
N.O.
COM.
CONTROL UNIT
GND
GRN
HOOD
MOTOR
A5
B5
B7
B9 Low
High
A1 A3 B1 B3 N.O.
E1
E2
DOOR
SENSING
SWITCH
PRIMARY
INTERLOCK
SWITCH
120 V AC.
60 Hz
HOOD
LAMP
HL
RY1
RY2
SECONDARY
INTERLOCK
RELAY
OVEN LAMP
RELAY
FM
OL
TTM
HOOD FAN
THERMAL
CUT OUT
HOOD
CAPACITOR
RY4
RY6
RY5
RY3
N.C.
CAVITY
THERMAL CUT-OUT
HL
F1
F2
F3
AH SENSOR
TROUBLESHOOTING GUIDE
Nevertouch anypart inthecircuitwithyourhandor anuninsulated toolwhilethepowersupplyisconnected.
Whentroubleshootingthe microwaveoven, itis helpfulto followthe Sequenceof Operationinperformingthechecks.Many
ofthepossiblecausesoftroublewillrequirethataspecifictestbeperformed.Thesetestsaregivenaprocedureletterwhich
will be found in the "Test Procedure "section.
IMPORTANT:
If the oven becomes inoperative because of a blown moni-
tor fuse, check the monitor switch, relay (RY1) secondary
interlock relay (RY2), door sensing switch and primary
interlockswitchbeforereplacingthemonitorfuse.If monitor
fuse is replaced, the monitor switch must also be replaced.
Use part FFS-BA016/KiT as an assembly.
IMPORTANT:
Whenever troubleshooting is performed with the power
supplycorddisconnected.Itmayin,somecases,beneces-
sary to connect the power supply cord after the outer case
has been removed, in this event,
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 the leads remain isolated from other
components and oven chassis by using insulation tape.
6. After that procedure, reconnect the power supply cord.
When the testing is completed
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. Reconnect the leads to the primary of the power
transformer.
5. Reinstall the outer case (cabinet).
6. Reconnectthepowersupplycord afterthe outercase is
installed.
7. Run the oven and check all functions.

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R-1511
LTOUCH CONTROL PANEL ASSEMBLY TEST
LQCK
CONTROL UNIT
AH SENSOR
SHORTED OR OPENED WIRING
The oven stops and "ERROR" is displayed or does not end during Sensor Cooking
condition. (Oven does not shut off after a cup of water is boiling by Sensor Cooking.)
Oven stops at 32 seconds after starting.
TEST PROCEDURE
PROBLEM
CONDITION
SENSOR
COOKING
CONDITION
POSSIBLE CAUSE
AND
DEFECTIVE PARTS
NOTE: For additional troubleshooting procedures, please refer back to the R-1500/1501/R1505/1506 base model
Service Manual.
TEST PROCEDURES
PROCEDURE
LETTER COMPONENT TEST
The touch control panel consists of circuits including semiconductors such as LSI, ICs, etc. Therefore,
unlike conventional microwave ovens, proper maintenance cannot be performed with only a voltmeter
andohmmeter.Inthisservicemanual,thetouchcontrolpanelassemblyisdividedintotwounits,Control
Unit and Key Unit, and also the Control Unit is divided into two units, LSI Unit and Power Unit, and
troubleshooting by unit replacement is described according to the symptoms indicated.
Before testing,
1) Disconnect the power supply cord, and then remove outer case. Refer to procedure of “ HOOD
EXHAUST LOUVER REMOVAL ”, “ REMOVAL OF OVEN FROM WALL ” and “ OUTER CASE
REMOVAL ”.
2) Open the door and block it open.
3) To discharge high voltage capacitor, wait for 60 seconds.
4) Remove two (2) screws holding the hood intake duct R to the ovencavity top plate and the base
plate R. And remove the hood intake duct R.
5) Disconnect the leads to the primary of the power transformer.
6) Ensure that these leads remain isolated from other components and oven chassis by using
insulation tape.
1. Key Unit.
NOTE ;
1) Check key unit ribbon connection before replacement.
2) Re-install the hood intake duct R with two (2) screws.
3) Re-install the outer case (cabinet).
4) Reconnect the power supply cord after the outer case is installed.
5) Run the oven and check all functions.
The following symptoms indicate a defective key unit.
a) When touching the pads, a certain pad produces no signal at all.
b) When touching a number pad, two figures or more are displayed.
c) When touching the pads, sometimes a pad produces no signal.
If the key unit is defective.
1) Disconnect the power supply cord, and then remove outer case.
2) Open the door and block it open.