Dacor PMOR3021B User manual

1
PMOR3021S
PMOR3021B
PMOR3021R
S94M245P3021S
PMOR3021S
PMOR3021B
PMOR3021R
OVER THE RANGE
MICROWAVE OVEN
MODELS
SERVICE MANUAL
This document has been published to be used for after
sales service only.
The contents are subject to change without notice.
dis tinctive applia nces
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
GENERAL INFORMATION................................................................................................................................. 5
OPERATION........................................................................................................................................................ 7
TROUBLESHOOTING GUIDE .......................................................................................................................... 11
TEST PROCEDURE .......................................................................................................................................... 13
TOUCH CONTROL PANEL ASSEMBLY........................................................................................................... 23
COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE .............................................................. 30
PICTORIAL DIAGRAM ...................................................................................................................................... 39
POWER UNIT CIRCUIT .................................................................................................................................... 40
LSI UNIT CIRCUIT............................................................................................................................................. 41
PRINTED WIRING BOARD ............................................................................................................................... 42
PARTS LIST ...................................................................................................................................................... 43
PACKING AND ACCESSORIES ....................................................................................................................... 48
Intheinterestofuser-safetytheovenshouldberestoredtoitsoriginalconditionandonlypartsidenticaltothosespecifiedshould
be used.
WARNING TO SERVICE PERSONNEL: Microwave ovens contain circuitry capable of producing very high voltage
and current. Contact with the following parts may result in a severe, possibly fatal, electrical shock. (Inverter unit
that includes High Voltage Capacitor, High Voltage Power Transformer, High Voltage Rectifier and Heat sink etc.,
and Magnetron, High Voltage Harness etc..)
Rev 1

2
PMOR3021S
PMOR3021B
PMOR3021R
PRECAUTIONS TO BE OBSERVED BEFORE AND
DURINGSERVICINGTOAVOIDPOSSIBLEEXPOSURE
TO EXCESSIVE MICROWAVE ENERGY
(a) Do not operate or allow the oven to be operated with the door open.
(b) Makethefollowingsafetychecksonallovenstobeservicedbeforeactivatingthemagnetronorothermicrowave
source, and make repairs as necessary: (1) interlock operation, (2) proper door closing, (3) seal and sealing
surfaces (arcing, wear, and other damage), (4) damage to or loosening of hinges and latches, (5) evidence of
dropping or abuse.
(c) Before turning on microwave power for any service test or inspection within the microwave generating
compartments,checkthe magnetron,waveguideor transmissionline,andcavityfor properalignment,integrity,
and connections.
(d) Any defective or misadjusted components in the interlock, monitor, door seal, and microwave generation and
transmissionsystemsshallberepaired,replaced,oradjustedbyproceduresdescribedinthismanualbeforethe
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 DACOR immediately @
1-800-793-0093.
If the unit operates with the door open, service person should 1) tell the user not to operate the oven and
2) contact DACOR and Food and Drug Administration's Center for Devices and Radiological Health
immediately.
Servicepersonnel shouldinform DACORof anycertified unitfound withemissions inexcess of4mW/cm2.
The owner of the unit should be instructed not to use the unit until the oven has been brought into
compliance.
DANGER CAUTION
HIGHVOLTAGE
Do not energize a microwave oven with the outer case cabinet removed, because a microwave oven
generates High Voltage in the circuit.
Ifyouintend tooperatetheoven employingthehighfrequency switchingpowerconvertercircuit,you should
take special precautions to avoid an electrical shock hazard.
The high voltage transformer, high voltage capacitor and high voltage diode have energized high voltage
potential approx. 8 KV.
Thealuminium heatsinkis connectedtothe switchingpowertransistor Collectorpole,and hasanenergized
high voltage potential approx. 650V peak.
DO NOT ACCESS THE HIGH VOLTAGE TRANSFORMER, HIGH VOLTAGE CAPACITOR, HIGH VOLT-
AGE DIODE AND HEAT SINK WHEN THE POWER SUPPLY IS CONNECTED TO AN ELECTRICAL
OUTLET.

1
PMOR3021S
PMOR3021B
PMOR3021R
WARNINGTO 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)
Inverter unit that includes High Voltage Capacitor,
High Voltage Power Transformer, High Voltage
Rectifier, Heat sink etc., and Magnetron, High
Voltage Harness etc..
Read the Service Manual carefully and follow all
instructions.
Before Servicing
1. Disconnect the power supply cord , and then
remove outer case.
2. Open the door and block it open.
3. Todischargehighvoltagecapacitor,waitfor60seconds.
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(thatistheconnectingleadofthehigh-
voltage rectifier) against the chassis with the use of an
insulated screwdriver.
Whenever troubleshooting is performed the power supply
mustbedisconnected.Itmayin,somecases,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. Todischargehighvoltagecapacitor,waitfor60seconds.
4. Disconnect the leads to the primary of the inverter unit.
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. Todischargehighvoltagecapacitor,waitfor60seconds.
4. Reconnect the leads to the primary of the inverter unit.
5. Reinstall the outer case (cabinet).
6. Reconnect the power supply cordafter theouter case 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. Reconnect the power supply cordafter theouter case 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.When the two minuteshaselapsed(timer at zero)
carefully check that the water is now hot. If the water
remainscoldcarryoutBeforeServicing procedureandre-
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

2
PMOR3021S
PMOR3021B
PMOR3021R
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
byapurchaser, and thereafter(throughtheusefullifeof the oven),5mW/cm2atanypoint5cmor morefromtheexternal
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 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:
Surveyinstrumentsthatcomply with the requirement for instrumentation as prescribedby the performancestandard
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 20o±5C (68oF) 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.
Theplacing of this standardload inthe ovenisimportantnot only to protect theoven,butalsoto insure that anyleakage
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,
and that the primary interlock switch and secondary interlock switch do turn the oven OFF before any door movement.
NOTE: After servicing, record data on service invoice and microwave leakage report.
SERVICING FOR INVERTER UNIT
WARNING
Thisinverterunitcontainscircuitrycapableofproducinghighvoltageand highcurrent.Contactwith anypart
of the high voltage will result in electrocution.
DO NOT ACCESS ANY PARTS OF INVERTER UNIT WITH POWER SUPPLY CONNECTED.
DO NOT OPERATE INVERTER UNIT ITSELF.
It is dangerous because this unit contains high voltage components.

3
PMOR3021S
PMOR3021B
PMOR3021R
SERVICE MANUAL
MICROWAVE OVENS
PMOR3021S/PMOR3021B/PMOR3021R
FOREWORD
This Manual has been prepared to provide Dacor Service Personnel
with Operation and Service Information for the DACOR MICRO-
WAVE OVENS, PMOR3021S, PMOR3021B and PMOR3021R.
It is recommended that service personnel carefully study the entire
text of this 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 no 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;
Inverter unit that includes High Voltage Capacitor, High
Voltage Power Transformer, High Voltage Rectifier, Heat
sink, etc., and Magnetron, High Voltage Harness etc.;
If provided, Vent Hood, Fan assembly, Cooling Fan Motor.
Allthepartsmarked“*”onpartslistareusedatvoltagesmorethan
250V.
Removaloftheouterwrappergivesaccessto voltage above 250V.
Allthepartsmarked“∆”onpartslistmaycauseunduemicrowave
exposure, by themselves, or when they are damaged, loosened
or removed.
PRODUCT DESCRIPTION
GENERAL INFORMATION
OPERATION
TROUBLESHOOTING GUIDE AND
TEST PROCEDURE
TOUCH CONTROL PANEL
COMPONENT REPLACEMENT
AND ADJUSTMENT PROCEDURE
WIRING DIAGRAM
PARTS LIST
1440 Bridge Gate Dr.
Diamond Bar, CA 91765
dis tinctive applia nces
dis tinctive applia nces

4
PMOR3021S
PMOR3021B
PMOR3021R
ITEM DESCRIPTION
Power Requirements 120 Volts / 12 Amperes
60 Hertz
Single phase, 3 wire grounded
Power Output 1200 watts (IEC TEST PROCEDURE)
Operating frequency of 2450MHz
Case Dimensions Width 29-15/16"
Height 17"
Depth 15- 9/16"
Cooking Cavity Dimensions Width 22-9/16"
Height 10-9/16"
2.1 Cubic Feet Depth 15"
Hood lamp 2 bulbs, 20W x 2, Incandescent light bulbs
Hood fan Approx. 300 C.F.M./ 270 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
SENSOR CENTER pads, MEAL TIME pads
HELP GUIDE pad, KEEP WARM PLUS pad, EASY DEFROST pad
SHORT CUTS pads, Numer selection pads, POWER LEVEL pad
Timer/Clock pad, Stop/Clear pad, START/EAST MINUTE pad
FAN: HI/LO, LIGHT: HI/LO
Oven Cavity Light 20W x 1 Incandescent light bulb
Safety Standard UL Listed FCC Authorized
DHHS Rules, CFR, Title 21, Chapter 1, Subchapter J
Canadian Standards Association
Health CANADA, Industry Canada
Weight Approx. 44 lbs.
PRODUCT SPECIFICATION

5
PMOR3021S
PMOR3021B
PMOR3021R
1
2
4
3
7
11
8
8
10 109
6
8
5
GENERAL INFORMATION
GROUNDING INSTRUCTIONS
This oven is equipped with a three prong grounding plug. It must be plugged into a wall receptacle that is properly installed
and grounded in accordance with the National Electrical Code and local codes and ordinances.
In the event of an electrical short circuit, grounding reduces the risk of electric shock by providing an escape wire for the
electric current.
WARNING: Improper use of the grounding plug can result in a risk of electric shock.
Electrical Requirements
The oven is equipped with a 3-prong grounding plug. DO NOT UNDER ANY CIRCUMSTANCES CUT OR REMOVE THE
GROUNDING PIN FROM THE PLUG.
Thepowersupplycordandplugmustbeconnectedtoaseparate120VoltAC,60Hz,15Amp.ormorededicatedline,using
agroundedreceptacle.ThereceptacleshouldbelocatedinsidethecabinetdirectlyabovetheMicrowaveOven/Hoodsystem
mounting location.
OVEN DIAGRAM
1. Oven door with see-through window.
2. Door hinges.
3. Oven lamp.
It will light when oven is operating or door is open.
4. Door latches.
The oven will not operate unless the door is securely closed.
5. One touch door open button
6. Auto-Touch control panel.
7. Timer display: Digital display, 99 minutes 00 seconds.
8. Ventilation openings.
9. Light Cover.
10.Grease filters.
11. Power supply cord
3-Pronged Plug Grounded
Receptacle Box
Grounding Pin
3-Pronged Receptacle

6
PMOR3021S
PMOR3021B
PMOR3021R
NOTE:
Some one-touch cooking features such as "MINUTE PLUS" are disabled after three minutes when the oven
is not in use. These features are automatically enabled when the door is opened and closed or the STOP/
CLEAR pad is pressed.
PMOR3021S

7
PMOR3021S
PMOR3021B
PMOR3021R
OPERATION
DESCRIPTION OF OPERATING SEQUENCE
Thefollowingisadescriptionofcomponentfunctionsduring
oven operation.
OFF CONDITION
Closingthedooractivatesthestopswitch,primaryinterlock
switchandsecondaryinterlockswitch.(Inthiscondition,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 flashing "88 : 88".
To set any program or set the clock, you must first
touch the STOP/CLEAR button. The display will clear,
and " : " will appear .
COOKING CONDITION
ProgramdesiredcookingtimetouchingtheNUMBERpads.
When the START button is touched, the following opera-
tions occur:
1. The contacts of relays are closed and components
connected to the relays are turned on as follows.
(For details, refer to Figure O-2)
RELAY CONNECTED COMPONENTS
RY1 Oven lamp / Fan motor / Stirrer motor
RY3, RY4 Hood fan motor
2. 120 volts A.C. is supplied to the inverter unit and is
convertedinordertopowerofthemagnetronbythehigh
frequency switching power circuit. The frequency is
approx. 33 _45 KHz.
3. The filament winding voltage of H.V. transformer heats
themagnetronfilamentandtheH.V.windinggivesahigh
voltage approx. 2 KV to activaite a voltage doubler
circuit.Thenapprox.4KVpeakvoltagepowerissupplied
to the magnetron cathode terminal.
4. The microwave energy produced by the magnetron is
channelled through the waveguide into the cavity feed-
box, and then into the cavity where the food is placed to
be cooked.
5. Upon completion of the cooking time, the inverter unit,
oven lamp, etc. are turned off, and the generation of
microwaveenergyisstopped.Theovenwillreverttothe
OFF condition.
6. Whenthedoorisopenedduringacookcycle,themonitor
switch,stopswitch,secondaryinterlockswitchandprimary
interlock switch are activated with the following results.
Thecircuitstothestirrermotor,thecoolingfanmotor,the
turntable motor, and the inverter unit are de-energized,
and the touch screen displays the time still remaining in
the cook cycle when the door was opened.
7. Themonitorswitchiselectricallymonitoringtheoperation
of the secondary interlock switch and primary interlock
switch and is mechanically associated with the door so
that it will function in the following sequence.
(1) When the door opens from a closed position, the
primary interlock switch and secondary interlock
switch open their contacts, and then the monitor
switch contacts close. And contacts of the relay
(RY1) remain closed.
(2) When the door is closed from the open position, the
monitor switch contacts first open and the stop
switch contacts open, and then the contacts of the
secondary interlock switch and primary interlock
switch close. And contacts of the relay (RY1) open.
If the secondary interlock switch and primary interlock
switch fail with their contacts closed when the door is
opened, the closing of the monitor switch contacts will form
ashortcircuitthroughthemonitorfuse,secondaryinterlock
switch,primaryinterlockswitchand relay(RY1)causingthe
monitor fuse to blow.
VARIABLE COOKING
When Variable Cooking Power is programmed, the 120
volts A.C. is supplied to the inverter unit which is operated
bythecontrolunit.Microwavepoweroperationisasfollows:
The oven can be set for any of 11 power levels: 0% to
100%(HIGH).The variable cooking powerless than40%is
programmedattheratioofONtimeandOFFtime within 32
sec./ cycle time base.
CONNECTION BETWEEN POWER SETTING AND ON/
OFF TIME OF INVERTER UNIT.
OUTPUT POWER SETTING ON TIME OFF TIME
Power 100%
Power 90%
Power 80%
Power 70% Continue operation
Power 60%
Power 50%
Power 40% 26 sec. 6 sec.
Power 30% 22 sec. 10 sec.
Power 20% 16 sec. 16 sec.
Power 10% 8 sec. 24 sec.
Power 0% 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.
SENSOR COOKING CONDITION
UsingtheSensorcookingfunctionthefoodiscookedwithout
figuringtime,powerlevelorquantity.Whentheovensenses
enough steam from the food, it relays the information to its
microprocessor which will calculate the remaining cooking
timeandpowerlevelneededforbestresults.Whenthefood
is cooked, water vapor is developed. The sensor “senses”
the vapor and its resistance increases gradually. When the

8
PMOR3021S
PMOR3021B
PMOR3021R
VENTILATION METHODS HOT AIR EXHAUST
1. VERTICAL VENTING
For this venting method, hot air rising from the
conventional range below is drawn in by the hood fan
motorthroughthegreasefiltersattherightandleftsides
of the base cover, up through the right and left sides of
theovencavity,then discharged verticallyatrearcenter
top of the oven, into the customer's vent system.
: AIR FLOW
resistance reaches the value set according to the menu,
supplementary cooking is started. The time of supplemen-
tary cooking is determined by experiment with each food
category and input into the LSI.
An example of how sensor works: (BAKED POTATOES)
1. Potatoes at room temperature. Vapor is emitted very
slowly.
2. HeatPotatoes.Moistureandhumidityisemittedrapidly.
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
the operation manual.
NOTE: The oven should not be operated on SENSOR
immediately after plugging in the unit. Wait two
minutes before cooking on SENSOR.
2. Thecoilofshut-offrelay(RY-1)isenergized,theturntable
motor, oven lamp and cooling fan motor are turned on,
but the inverter unit is not turned on.
3. After about 32 seconds, the cook relay (RY-2) is
energized. The power transformer is turned on,
microwaveenergyisproduced and first stageisstarted.
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,the displayswitchesoverto theremainingcooking
time and the timer counts down to zero.
At this time, the door may be opened to stir, turn, or
season food.
5. Whenthe timer reaches zero, anaudible signal sounds.
The shut-off relay is de-energized and the inverter unit,
oven lamp, etc. are turned off.
6. OpeningthedoorortouchingtheSTOP/CLEARpad,the
timeofday will reappearonthedisplayand theovenwill
revert to an OFF condition.
2. HORIZONTAL VENTING
The air handing is the same as VERTICAL VENTING
exceptthatthefinalairdischargeisdirectedhorizontally
outfromthetoprearoftheovenintothecustomer'svent
system. : AIR FLOW
MICROWAVE
MICROWAVE
AH SENSOR
3. RE-CIRCULATION (INSIDE VENTING)
The air handing is the same as VERTICAL VENTING
exceptthatthefinalairdischargeisdirectedhorizontally
through the upper front of the oven into the kitchen. In
this case, the accessory charcoal filter RK-260 must be
provided to filter the air before it leaves the oven.
: AIR FLOW
GREASE
FILTER
HOOD FAN MOTOR TO DUCT
TO DUCT
HOOD
INTAKE
DUCT R
TO DUC
T
GREASE
FILTER
HOOD FAN MOTOR
HOOD
INTAKE
DUCT R
HOOD EXHAUST
LOUVER
HOOD FAN MOTOR CHARCOAL FILTER
GREASE
FILTER
HOOD
INTAKE
DUCT R

9
PMOR3021S
PMOR3021B
PMOR3021R
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED
2. COOKING TIME PROGRAMMED
3. VARIABLECOOKING CONTROL "HIGH"
4. "START" PAD TOUCHED
Figure O-2. Oven Schematic-Cooking Condition
Figure O-1. Oven Schematic-Off Condition
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED
2. CLOCK APPEARS ON DISPLAY
WHT
BLU RED
BLK
BLU
WHT
RED
BLK
RED
RED
FUSE
20A
RED
ORG
RED
RED
A5
RY3
A7
High
BLK
BLK
WHT
HOOD
CAPACITOR
HOOD
MOTOR
GRY
YLW
BLU
YLW
RED
RY4
RY5
BLU
BLU
BLU
BLU
BRN or PPL
YLW or ORG
N. O.
OVEN
LAMP
RELAY
COM.
GRY
WHT RED
WHT
BRN
BLK BLK
RED
STIRRER
MOTOR
WHT
BRN
BRN
BRN
RED
WHT
RED
BLU
RED RED
E1
E2
BLK
GRN
STOP
SWITCH
WHT
RED
BLU
WHT
RY1
ORG RED
C3
B1
RY6
C5
B3
A1 A3 A9 HUMIDITY
SENSOR
F3
F2
F1
GRY
WHT
COM
N.C.
FAN
MOTOR
WITH
TEMP. FUSE
MAGNETRON
120VAC
60Hz.
L
OVEN
LAMP
NOISE FILTER
THERMAL
HOOD FAN
CUT OUT
YLW
RED
CUTOUT
OVEN THERMAL
CONTROLUNIT
ORG
N.O.
COM
PRIMARY
INTERLOCK
SWITCH
N.O.COM
BLK
A3
A1 FA
F
MONITOR
SWITCH
AC3
M
INVERTER
UNIT
WHT
BLU
GRY
HOOD
LAMP
HL HL
BLU
RED
NC
Low
SECONDARY
INTERLOCK
SWITCH
H1
H3
NOTES:
1. Circuits / Wire Colors subject to change without notice.
2. Terminal that located to the right side on the lamp socket's back view
must be connected to neutral wire.
3. Only certain models use the absolute humidity sensor
H
N
GND
GRN LVT
C1 C2
C4
C3
WHT
BLU RED
BLK
BLU
WHT
RED
BLK
RED
RED
FUSE
20A
RED
ORG
RED
RED
A5
RY3
A7
High
BLK
BLK
WHT
HOOD
CAPACITOR
HOOD
MOTOR
GRY
YLW
BLU
YLW
RED
RY4
RY5
BLU
BLU
BLU
BLU
BRN or PPL
YLW or ORG
N. O.
OVEN
LAMP
RELAY
COM.
GRY
WHT RED
WHT
BRN
BLK BLK
RED
STIRRER
MOTOR
WHT
BRN
BRN
BRN
RED
WHT
RED
BLU
RED RED
E1
E2
BLK
GRN
STOP
SWITCH
WHT
RED
BLU
WHT
RY1
ORG RED
C3
B1
RY6
C5
B3
A1 A3 A9 HUMIDITY
SENSOR
F3
F2
F1
GRY
WHT
COM
N.C.
FAN
MOTOR
WITH
TEMP. FUSE
MAGNETRON
120VAC
60Hz.
L
OVEN
LAMP
NOISE FILTER
THERMAL
HOOD FAN
CUT OUT
YLW
RED
CUTOUT
OVENTHERMAL
CONTROLUNIT
ORG
N.O.
COM
PRIMARY
INTERLOCK
SWITCH
N.O.COM
BLK
A3
A1 FA
F
MONITOR
SWITCH
AC3
M
INVERTER
UNIT
WHT
BLU
GRY
HOOD
LAMP
HL HL
BLU
RED
NC
Low
SECONDARY
INTERLOCK
SWITCH
H1
H3
NOTES:
1. Circuits / Wire Colors subject to change without notice.
2. Terminal that located to the right side on the lamp socket's back view
must be connected to neutral wire.
3. Only certain models use the absolute humidity sensor
H
N
GND
GRN LVT
C1 C2
C4
C3

10
PMOR3021S
PMOR3021B
PMOR3021R
DESCRIPTION AND FUNCTION OF COMPONENTS
monitor switch contacts.
CAUTION: BEFORE REPLACING A BLOWN MONITOR
FUSE TEST THE STOP SWITCH, PRIMARY
INTERLOCK SWITCH,SECONDARYINTER-
LOCKSWITCHANDMONITORSWITCHFOR
PROPER OPERATION. (REFER TO CHAP-
TER "TEST PROCEDURE").
NOTE: MONITORFUSE ANDSWITCHARE REPLACED
AS AN ASSEMBLY
THERMAL CUT-OUT (HOOD )
This thermal cut-out located on the right base plate. It is
designed to automatically turn on the hood fan motor
whenever the hot air rising from the conventional range
belowcauses the temperature atthe thermalcut-outtorise
to 140oF (60oC) or higher, thus removing this hot air from
aroundmicrowaveoven.Whenthetemperaturearoundthe
thermal cut-out drops to 113oF (45oC) or lower, the thermal
cut-out shuts off the hood fan motor.
THERMAL CUT-OUT (OVEN )
Thisthermalcut-out is locatedonthetopof the ovencavity.
It is designed to prevent damage to the oven unit if the food
in the oven catches fire due to overheating produced by
improper setting of cooking time or failure of control unit.
Under normal operation, the thermal cut-out remains
closed. However, the thermal cut-out will open at 293oF
(145oC) causing the oven to shut down.
COOLING FAN MOTOR
The cooling fan motor drives a blade which draws external
cool air. This cool air is directed through the air vanes
surrounding the magnetron and cools the magnetron. This
air is channelled through the oven cavity to remove steam
and vapors given off from the heating foods. It is then
exhausted through the exhausting air vents at the oven
cavity.
HOOD FAN MOTOR
The hood fan motor is a two-speed, single-phase, double
pole induction type, requiring a hood fan capacitor. It is
located outside the upper rear part of the oven cavity, is to
remove, from around the oven, hot air rising from the
conventional electric or gas range over which it is installed.
This air is then expelled either vertically or horizontally
through the customer supplied duct system, or discharged
back into the kitchen.
STIRRER MOTOR
Thestirrermotorsdrivethestirrerfanstostirthemicrowave
radiation from the waveguide.
HOOD LAMP
The hood lamps are mounted at the hood lamp angle. The
hood lamps can be turned off and on by touching the Light
Options pad. And also the brightness can be varied to high
or low by touching the Light Options pad.
DOOR OPEN MECHANISM
The door is opened by pushing the open button on the
control panel, refer to the Figure D-1.
Whentheopenbuttonispushed,theopenbuttonpushesup
theopenlever,andthentheopenleverpushesupthelatch
head.Thelatchheadsaremovedupwardandreleasedfrom
latch hook. Now the door will open.
Figure D-1. Door Open Mechanism
STOP, PRIMARY INTERLOCK AND SECONDARY
INTERLOCK SWITCHES
The secondary interlock switch is mounted in the lower
position of the latch hook and the stop switch is mounted in
the upper position of the latch hook. The primary interlock
switch is also in the upper position of the latch hook. They
areactivatedbythelatchheadsonthedoor.Whenthedoor
is opened, the switches interrupt the circuit to all compo-
nents.A cookcyclecannottake placeuntilthedoorisfirmly
closed thereby activating both interlock switches.
MONITOR SWITCH
Themonitorswitchisactivated(thecontactsopened)bythe
latch head on the door while the door is closed. The switch
is intended to render the oven inoperative by means of
blowing the monitor fuse when the contacts of the primary
interlock switch and secondary interlock switch fail to open
when the door is opened.
Functions:
1. When the door is opened, the monitor switch contact
close (to the ON condition) due to their being normally
closed. At this time the primary interlock switch and
secondary interlock switch are in the OFF condition
(contactsopen)duetotheirbeingnormallyopencontact
switches. And the contacts of relay (RY1) are in the ON
condition (contacts close).
2. Asthedoorgoestoaclosedposition,themonitorswitch
contacts are first opened and the stop switch contacts
close, and then the primary interlock switch and the
secondary interlock switch contacts close. (On opening
the door, each of these switches operate inversely.)
3. If the door is opened, and the primary interlock switch
andsecondaryinterlockswitch contacts fail toopen,the
monitor fuse blows simultaneously with closing of the
Latch hook
Stop switch
Latch heads
Monitor switch
Secondary
interlock switch
Primary
interlock switch
O
p
en lever
Door

11
PMOR3021S
PMOR3021B
PMOR3021R
TROUBLESHOOTING GUIDE
Nevertouchanypartinthecircuitwithyourhandoranuninsulatedtoolwhilethepowersupplyisconnected.
Whentroubleshootingthemicrowaveoven,itishelpfultofollowtheSequenceofOperationinperformingthechecks. Many
ofthepossiblecausesoftroublewillrequirethataspecifictestbeperformed.Thesetestsaregivenaprocedureletterwhich
will be found in the "Test Procedure "section.
IMPORTANT: If the oven becomes inoperative because of a blown monitor fuse, check the monitor switch, relay (RY1)
primary interlock switch and secondary interlock switch before replacing the monitor fuse. 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 supply cord disconnected. It may in, some cases,
be necessary 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. To discharge high voltage capacitor, waite for 60 seconds.
4. Disconnect the leads to the primary of the inverter unit.
5. Ensurethatthe leadsremainisolatedfromothercomponentsand ovenchassisbyusing insulationtape.
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. To discharge high voltage capacitor, waite for 60 seconds.
4. Reconnect all leads removed from components during testing.
5. Reinstall the outer case (cabinet).
6. Reconnect the power supply cord after the outer case is installed.
7. Run the oven and check all functions.

12
PMOR3021S
PMOR3021B
PMOR3021R CK = Check / RE = Replace
POSSIBLE CASE AND
DEFECTIVE PARTS
PROBLEM
TEST PROCEDURE
CONDITION
OFF
CONDITION
IDLE
CONDITION
MICROWAVE
COOKING
CONDITION
SENSOR
COOKING
CONDITION
Home fuse blows when power cord is plugged into wall receptacle. Monitor fuse blows when power cord is plugged into wall receptacle. Display does not illuminate when power cord is first plugged into wall receptacle. Display does not operate properly when STOP/CLEAR key is touched. (The time of day should appear on the display with beep sound during normal con- dition.) Oven lamp does not light with door is opened. Hood fan motor operates when power cord is first plugged into wall receptacle. Temperature of oven base seems more than 140°F (60°C) because of operation of the range below. But hood fan motor does not turn on automatically. (Normal- ly, food fan motor should be operating at low speed.) Hood lights do not turn on when Light pad is pressed. Hood fan motor does not rotate at all with touched Fan pad. Speed of the hood fan motor does not change when the Fan Options pad is touched for this function. Oven lamp does not light in cook cycle. (But it does light when door is opened.) Fan motor does not operate. (Oven lamp and strrer motor operate.) Oven does not go into cook cycle when START pad is touched Oven seems to be operating but little or no heat is produced in oven load. (Food incompletely cooked or not cooked at all at end of cook cycle.) Oven goes into a cook cycle but extremely uneven heating is produced in oven load (food). Variable cooking does not operate properly except Cooking Power 100% mode. Stirrer motor does not operate. (Other parts operate.) Oven goes into EASY DEFROST but food is not defrosted well. 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.
P NOISE FILTER
CK LOW VOLTAGE
CK NO POWER AT OUTLET
RE SHORTED IN POWER CORD
CK OPENED OR SHORTED WIRING
CK HOOD MOTOR CAPACITOR
RE HOOD LAMP OR SOCKET
RE STIRRER MOTOR
RE FAN MOTOR
RE OVEN LAMP OR SOCKET
O HUMIDITY SENSOR (R2120J)
N FOIL PATTERN ON P.W.B.
M EASY DEFROST
L RELAY (RY-4)
L RELAY (RY-3)
L RELAY (RY-5, RY-6)
L RELAY (RY-1)
K KEY UNIT
J CONTROL UNIT
I HOOD FAN MOTOR
H HOOD THERMAL CUT-OUT
G MONITOR FUSE
F MONITOR SWITCH
E STOP SWITCH
D PRIMARY INTERLOCK SWITCH
D SECONDARY INTERLOCK SWITCH
C OVEN THERMAL CUT-OUT
B INVERTER UNIT
A MAGNETRON

13
PMOR3021S
PMOR3021B
PMOR3021R
BINVERTER UNIT TEST
TEST PROCEDURES
PROCEDURE
LETTER COMPONENT TEST
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
4. Totest foran openfilament, isolatethemagnetronfromthehighvoltage circuit.A continuitycheck across
the magnetron filament leads should indicate less than 1 ohm.
5. Totestfor a shorted magnetron,connecttheohmmeter leads between themagnetronfilament leads and
chassis ground. This test should indicate an infinite resistance. If there is little or no resistance the
magnetron is grounded and must be replaced.
6. Reconnect all leads removed from components during testing.
7. Reinstall the outer case (cabinet).
8. Reconnect the power supply cord after the outer case is installed.
9. Run the oven and check all functions.
MICROWAVE OUTPUT POWER
The following test procedure should be carried out with the microwave oven in a fully assembled condition
(outer case fitted).
HIGH VOLTAGES ARE PRESENT DURING THE COOK CYCLE, SO EXTREME CAUTION SHOULD BE
OBSERVED.
Poweroutputofthemagnetroncanbemeasuredbyperformingawatertemperaturerisetest.Thistestshould
only be used if above tests do not indicate a faulty magnetron and there is no defect in the following
components or wiring: inverter unit. This test will require a 16 ounce (453cc) measuring cup and an accurate
mercurythermometerorthermocoupletypetemperaturetester.Foraccurateresults,thefollowingprocedure
must be followed carefully:
1. Fill the measuring cup with 16 oz. (453cc) of tap water and measure the temperature of the water with a
thermometerorthermocoupletemperaturetester.Stirthethermometerorthermocouplethroughthewater
until the temperature stabilizes. Record the temperature of the water.
2. Place the cup of water in the oven. Operate oven at POWER 10(HIGH) selecting more than 60 seconds
cook time. Allow the water to heat for 60 seconds, measuring with a stop watch, second hand of a watch
or the digital read-out countdown.
3. Remove the cup from the oven and again measure the temperature, making sure to stir the thermometer
or thermocouple through the water until the maximum temperature is recorded.
4. Subtract the cold water temperature from the hot water temperature. The normal result should be 39.2 to
63oF(21.8 to 35oC) rise in temperature. If the water temperatures are accurately measured and tested for
the required time period the test results will indicate if the magnetron tube has low power output (low rise
in water temperature) which would extend cooking time or high power output (high rise in water
temperature) which would reduce cooking time. Because cooking time can be adjusted to compensate
forpoweroutput,the magnetron tube assembly shouldbereplacedonly if the water temperaturerisetest
indicates a power output well beyond the normal limits. The test is only accurate if the power supply line
voltage is 120 volts and the oven cavity is clean.
AMAGNETRON ASSEMBLY TEST
WARNING: DO NOT TOUCH THE COMPONENTS OF THE INVERTER UNIT WHILE INVERTER
UNIT IS ENERGIZED. IT IS DANGEROUS BECAUSE THIS HAS HIGH VOLTAGE
COMPONENTS.
CAUTION: DO NOT OPERATE INVERTER UNIT BY ITSELF.
CAUTION: DO NOT CONNECT THE OVEN TO WALL OUTLET WITHOUT THE OUTER CASE
INSTALLED.
Before checking the inverter unit, curry out following 4 steps.
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
4. Make sure that the wire leads and the connectors are connected correctly to the inverter unit, control unit
and magnetron.

14
PMOR3021S
PMOR3021B
PMOR3021R
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
4. A continuity check across the thermal cut-out terminals should indicate a closed circuit unless the
temperature of the thermal cut-out reaches approximately 293oF(145oC).
An open thermal cut-out indicates overheating of the oven, exchange the oven thermal cut-out and
checkinsideofovencavityandforimpropersettingofcookingtimeoroperationofcontrolunit.Check
forrestrictedairflowthroughtheventholesoftheovencavity,especiallythecoolingfanandairguide.
5. Reconnect all leads removed from components during testing.
6. Reinstall the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
CAUTION: IF THE THERMAL CUT-OUT INDICATES AN OPEN CIRCUIT AT ROOM TEMPERA-
TURE, REPLACE THERMAL CUT-OUT.
COVEN THERMAL CUT-OUT TEST
Chart for checking the defective inverter unit
No power at full power output cooking
Magnetron is defective. Exchange the magnetron.
Exchange the Inverter unit
Brown monitor fuse
The secondary interlock switch, primary interlock
switch and the monitor switch are operating properly.
YES
Exchange the Inverter unit
TEST PROCEDURES
PROCEDURE
LETTER COMPONENT TEST
NO
Check the switches according to
the switch Test Procedure
YES
NO
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
4. Isolatetheswitchandconnecttheohmmetertothecommon(COM.)andnormallyopen(NO)terminal
of the switch. The meter should indicate an open circuit with the door open and a closed circuit with
thedoorclosed.Ifimproperoperation is indicated, replace the primary interlock switch or secondary
interlock switch.
5. Reconnect all leads removed from components during testing.
6. Reinstall the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
DPRIMARY INTERLOCK SWITCH AND SECONDARY INTERLOCK SWITCH TEST
STOP SWITCH
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
ESTOP SWITCH TEST

15
PMOR3021S
PMOR3021B
PMOR3021R
TEST PROCEDURES
PROCEDURE
LETTER COMPONENT TEST
4. Isolatetheswitchandconnecttheohmmetertothecommon(COM.)andnormallyopen(NO)terminal
of the switch. The meter should indicate an open circuit with the door open and a closed circuit with
the door closed. If improper operation is indicated, replace the stop switch.
5. Reconnect all leads removed from components during testing.
6. Reinstall the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
NOTE: If the stop switch contacts fail in the open position and the door is closed, the cooling fan motor,
stirrer motor and oven light will be activated by RY1.
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
4. Before performing this test, make sure that the secondary interlock switch and the primary interlock
switch are operating properly, according to the above Switch Test Procedure. Disconnect the wire
lead from the monitor switch (COM) terminal. Check the monitor switch operation by using the
ohmmeter as follows. When the door is open, the meter should indicate a closed circuit. When the
monitor switch actuator is pushed by a screw driver through the lower latch hole on the front plate
of the oven cavity with the door opened (in this condition the plunger of the monitor switch is pushed
in), the meter should indicate an open circuit. If improper operation is indicated, the switch may be
defective. After testing the monitor switch, reconnect the wire lead to the monitor switch (COM)
terminal and check the continuity of the monitor circuit.
5. Reconnectallleadsremovedfrom
components during testing.
6. Reinstall the outer case (cabinet).
7. Reconnect the power supply cord
after the outer case is installed.
8. Run the oven and check all
functions.
FMONITOR SWITCH TEST
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
4. If the monitor fuse is blown when the door is opened, check the primary interlock switch, secondary
interlockswitchandmonitorswitchaccordingtothe"TESTPROCEDURE"forthoseswitchesbefore
replacing the blown monitor fuse.
CAUTION: BEFORE REPLACING A BLOWN MONITOR FUSE, TEST THE PRIMARY INTERLOCK
SWITCH, SECONDARY INTERLOCK SWITCH AND MONITOR SWITCH FOR PROPER
OPERATION.
If the monitor fuse is blown by improper switch operation, the monitor fuse and monitor switch must
be replaced with "monitor fuse and monitor switch assembly" part number FFS-BA016/KIT, even if
the monitor switch operates normally. The monitor fuse and monitor switch assembly is comprised
of a 20 ampere fuse and switch.
5. Reconnect all leads removed from components during testing.
6. Re-install the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
GBLOWN MONITOR FUSE TEST
Secondary
Interlock
Switch
Monitor
Switch
Screw Driver
Ohmmeter
Black White/Blue

16
PMOR3021S
PMOR3021B
PMOR3021R
6-PINCONNECTOR
OF HOOD FAN MOTOR
TEST PROCEDURES
PROCEDURE
LETTER COMPONENT TEST
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
4. A continuity check across the thermal cut-out terminals should indicate an open circuit unless the
temperatureofthethermal cut-out reaches approximately 140oF(60oC)ormore.At that temperature, the
contacts will close. The thermal cut-out opens automatically at approximately 113oF(45oC).
5. Reconnect all leads removed from components during testing.
6. Reinstall the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
HHOOD THERMAL CUT-OUT TEST
IHOOD FAN MOTOR TEST
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
4. If the motor does not turn, touch the FAN HI/LO pad once (set hood fan motor power "HIGH") and check
voltage between pins "1" and "2" (Blue and Black wires) of the 6 pin connector. If 120 Volts appear and
thehoodcapacitor isgood,replace the hoodfanassembly. If120Volts does notappear,check themotor
circuit. The resistance values of motor terminals are as follows:
5. Reconnect all leads removed from components during testing.
6. Reinstall the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions. Resistance between;
BLU (1) AND YLW (4) = 0 Ω(Shorted)
BLK (2) AND YLW (4) = 32 Ω
BLU (1) AND BLK (2) = 32 Ω
BLK (2) AND WHT (3) = 10 Ω
WHT (3) AND RED (5) = 20 Ω
32 Ω
10 Ω20 Ω
HOOD FAN
CAPACITOR
YLW
RED
BLU
BLK
1
2
3
WHT
4
5
123
45
BLU BLK WH
T
YLW RED
Thetouchcontrol panel consists of circuitsincludingsemiconductors such as LSI, ICs,etc.Therefore, unlike
conventional microwave ovens, proper maintenance cannot be performed with only a voltmeter and
ohmmeter.Inthisservicemanual,thetouch controlpanel assemblyisdividedintotwounits,Control Unitand
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
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 seven (7) screws holding the hood intake duct R to the oven cavity top plate, oven cavity
flange, fun duct, magnetron duct and the base plate R. And remove the hood intake duct R.
5) Disconnect the leads to the primary of the inverter unit.
6) Ensure that these leads remain isolated from other components and oven chassis by using insulation
tape.
JTOUCH CONTROL PANEL ASSEMBLY TEST

17
PMOR3021S
PMOR3021B
PMOR3021R
TEST PROCEDURES
PROCEDURE
LETTER COMPONENT TEST
1. Key Unit.
NOTE ;
1) Check key unit ribbon connection before replacement.
2) Re-install the hood intake duct R with seven (7) 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.
3) To discharge high voltage capacitor, wait for 60 seconds.
4) Replace the key unit.
5) Reconnect all leads removed from components during testing.
6) Re-install the outer case (cabinet).
7) Reconnect the power supply cord after the outer case is installed.
8) Run the oven and check all functions.
2. Control Unit.
The following symptoms indicate a defective control unit. Before replacing the control unit, perform the
Key unit test (Procedure K) to determine if control unit is faulty.
2-1 In connection with pads.
a) When touching the pads, a certain group of pads do not produce a signal.
b) When touching the pads, no pads produce a signal.
2-2 In connection with indicators
a) At a certain digit, all or some segments do not light up.
b) At a certain digit, brightness is low.
c) Only one indicator does not light.
d) The corresponding segments of all digits do not light up; or they continue to light up.
e) Wrong figure appears.
f) A certain group of indicators do not light up.
g) The figure of all digits flicker.
2-3 Other possible problems caused by defective control unit.
a) Buzzer does not sound or continues to sound.
b) Clock does not operate properly.
c) Cooking is not possible.
When testing is completed,
1) Disconnect the power supply cord.
2) Open the door and block it open.
3) To discharge high voltage capacitor, wait for 60 seconds.
4) Reconnect all leads removed from components during testing.
5) Re-install the hood intake duct R.
6) Re-install the outer case (cabinet).
7) Reconnect the power supply cord after the outer case is installed.
8) Run the oven and check all functions.
1. Disconnect the power supply cord.
2. Open the door and block it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
4. Remove the control panel assembly.
5. If the display fails to clear when the STOP/CLEAR pad is depressed, first verify the flat ribbon cable is
making good contact, verify that the stop switch operates properly; that is the contacts are closed when
the door is closed and open when the door is open. If the stop switch is good, disconnect the flat ribbon
cable that connects the key unit to the control unit and make sure the stop switch is closed (either close
the door or short the stop switch connecter). Use the Key unit matrix indicated on the control panel
KKEY UNIT TEST

18
PMOR3021S
PMOR3021B
PMOR3021R TEST PROCEDURES
PROCEDURE
LETTER COMPONENT TEST
schematic and place a jumper wire between the pins that correspond to the STOP/CLEAR pad making
momentary contact. If the control unit responds by clearing with a beep the key unit is faulty and must be
replaced. If the control unit does not respond, it is faulty and must be replaced. If a specific pad does not
respond, the above method may be used (after clearing the control unit) to determine if the control unit or
key pad is at fault.
6. Reconnect all leads removed from components during testing.
7. Re-install the control panel assembly.
8. Reconnect the power supply cord.
9. Run the oven and check all functions.
1. Disconnect the power supply cord, and then remove outer case. Refer to procedure of “HOOD 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 the hood intake duct R.
5. Disconnect the leads to the primary of the inverter unit.
6. Ensurethattheseleadsremain isolatedfromothercomponentsandovenchassisbyusinginsulationtape.
7. After that procedure, re-connect the power supply cord.
8. Check voltage between the Pin No. 3 of the 3 pin connector (C) and the normal open 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, RY3, RY4, RY5 and RY6 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.
RELAYSYMBOL OPERATIONALVOLTAGE CONNECTEDCOMPONENTS
RY1 Approx.25.0V D.C. Inverter unit/ Oven lamp/ Fan motor/ Stirrer motor
RY3 Approx.25.0V D.C. Hood motor(High/Low seclection)
RY4 Approx.25.0V D.C. Hoodmotor
RY5 Approx.25.0V D.C. Hoodlamp
RY6 Approx.25.0V D.C. Hoodlamp
9. Disconnect the power supply cord.
10. Open the door and block it open.
11. To discharge high voltage capacitor, wait for 60 seconds.
12. Reconnect all leads removed from components during testing.
13. Re-install the hood intake duct R.
14. Re-install the outer case (cabinet).
15. Reconnect the power supply cord after the outer case is installed.
LRELAY TEST
MEASY DEFROST TEST
(1) Open the door.
(2) Place one cup of water in the center of the turntable tray in the oven cavity.
(3) Touch the “EASY DEFROST” pad once. And then touch the number pad “ 2 ”.
(4) Touch the number pad “ 5 ”.
(5) Close the door.
G8 G9 G10 G11 G12
Melt2
97
G7
1
6
Soften
8
STOP
CLEAR
Popcorn
G6G5
G1 G2 G3
1
62
61
59 58 57 56 55 54 53 52
Dinner
Menu
Cook3450
60
START
EASY MINUTE
POWER
LEVEL
Warm Reheat
Breakfast
Menu
Lunch
Menu
Keep
Warm
Help
Guide
Easy
Defrost
FAN
HI / LO
Timer
Clock
LIGHT
HI / LO
G4