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7/25/2019 8178053 Job Aid Microwave Oven Hood Combination
FORWARDThis Job Aid, “Whirlpool Microwave Oven Hood Combination,” (Part No.8178053 ), provides thetechnician with information on the operation and service of the Whirlpool Microwave Oven HoodCombination. It is to be used as a training Job Aid and Service Manual. For specific informationon the model being serviced, refer to the “Use and Care Guide,” or “Tech Sheet” provided with themicrowave oven.
The Wiring Diagrams and Strip Circuits used in this Job Aid are typical and should be used for training purposes only. Always use the Wiring Diagram supplied with the product when servicingthe unit.
GOALS AND OBJECTIVESThe goal of this Job Aid is to provide detailed information that will enable the service technician toproperly diagnose malfunctions and repair the Microwave Oven Hood Combination.
The objectives of this Job Aid are to:
• Understand and follow proper safety precautions.
• Successfully troubleshoot and diagnose malfunctions.
• Successfully perform necessary repairs.
• Successfully return the microwave oven to proper operational status.
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GENERAL ............................................................................................................................... 1-1 Important Safety Information ................................................................................................ 1-1 Warning To Service Technicians ......................................................................................... 1-2 Precautions To Be Observed Before And During Servicing To Avoid
Possible Exposure To Excessive Microwave Energy ....................................................... 1-3 R.F. Leakage Test................................................................................................................ 1-4 Whirlpool Model & Serial Number Designations .................................................................. 1-5 Model & Serial Number Label And Tech Sheet Locations ................................................... 1-6 Specifications ....................................................................................................................... 1-7 Whirlpool Microwave Oven Warranty................................................................................. 1-11
THEORY OF OPERATION ..................................................................................................... 2-1 The Vent Motor Mounting Positions ..................................................................................... 2-1 The Oven Thermostat & Vent Motor Capacitor .................................................................... 2-2 The Vent & Turntable Motors ............................................................................................... 2-3
COMPONENT ACCESS ......................................................................................................... 3-1 Component Locations .......................................................................................................... 3-1 Removing The Turntable Motor & Cooktop Lamp Assembly ............................................... 3-2 Removing The Control Panel & Control Board .................................................................... 3-4 Removing The Door Switches.............................................................................................. 3-6 Removing The Oven Lamp Assembly.................................................................................. 3-7 Removing The Oven Thermostat, Line Fuse, & Power Cord ............................................... 3-8 Removing The Vent Motor Capacitor, The High Voltage Capacitor, & Rectifier ......................................................................................... 3-10 Removing The High Voltage Transformer.......................................................................... 3-11 Removing The Magnetron.................................................................................................. 3-12
Removing The Vent Motor ................................................................................................. 3-13 Removing The Oven Door, The Switch Actuators, And The Outer Glass ...................................................................................................... 3-14
COMPONENT TESTING ........................................................................................................ 4-1 Touch Panel Continuity ........................................................................................................ 4-1 The Turntable & Vent Motors ............................................................................................... 4-2 The Vent Motor Capacitor, Line Fuse, Oven Thermostat, & Door Switch ................................................................................................................... 4-3 The High Voltage Capacitor & Rectifier ............................................................................... 4-4 The High Voltage Transformer ............................................................................................. 4-5 The Magnetron..................................................................................................................... 4-6
Failure to do so could result in death or electrical shock.
Important safety messages have been pro-vided in this Job Aid. Always read and obey allsafety messages.
GENERALIMPORTANT SAFETY INFORMATION
Your safety and the safety of others is very important.
This is the safety alert symbol.
This symbol alerts you to haz-ards that can kill or hurt youand others.
All safety messages will be preceded by thesafety alert symbol and the word “WARNING.”
All safety messages will identify the hazard, tell
you how to reduce the chance of injury, and tellyou what can happen if the instructions are notfollowed.
WARNING
IMPORTANT SAFETYINSTRUCTIONS
Before touching any oven component or wir-ing, always unplug the oven from its power source and discharge the capacitor by using a20,000 ohm discharge resistor or use an insu-lated plastic handle screwdriver to short acrossthe capacitor terminals.
Check that the unit is grounded before trouble-shooting. Be careful of the high voltage circuits.Discharge any static charge from your body bytouching ground before handling any part of the circuitry on the control board. Electrostaticdischarge may damage the control circuit.
Do not touch oven components or wiring duringoperation. Attach meter leads with alligator clips when making operational tests.
For continued protection against radiationemission, replace only with these types of switches: Primary (Interlock) Switch: SZM-V16-FA-63 or VP-533A-OF; Secondary (Interlock)Switch: SZM-V01-FA-32; Interlock (Monitor)Switch: SZM-VI6-FA-62 or VP-532A-OF; OvenLamp Switch: SZM-V6-FA-31 or VP-331 A-OD.
It is neither necessary nor advisable to attemptmeasurement of high voltage.
Attaching the adaptor ground terminal to thewall receptacle cover screw does not groundthe appliance unless the cover screw is metaland not insulated and the wall receptacle isgrounded through the house wiring.
ESD problems are present everywhere. ESDmay damage or weaken the electronic con-trol assembly. The new control assemblymay appear to work well after repair is fin-ished, but failure may occur at a later datedue to ESD stress.
• Use an antistatic wrist strap. Connectthe wrist strap to a green ground con-nection point or unpainted metal in theappliance; or touch your finger repeat-edly to a green ground connection pointor unpainted metal in the appliance.
• Before removing the part from its pack-age, touch the antistatic bag to a green
ground connection point or unpaintedmetal in the appliance.
• Avoid touching electronic parts or ter-minal contacts. Handle the electroniccontrol assembly by the edges only.
• When repackaging the failed electroniccontrol assembly in an antistatic bag,observe the above instructions.
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To avoid possible exposure to microwave ra-diation or energy, visually check the oven for damage to the door and door seal beforeoperating any oven. Use a microwave surveymeter to check the amount of leakage beforeservicing. In the event the R.F. Ieakage ex-ceeds 4 mw/cm2 at 5 cm, appropriate repair must be made before continuing to service theunit. Check interlock function by operating thedoor latch. The oven cook cycle should cut off before the door can be opened.
The door and latching assembly contains theradio frequency energy within the oven. Thedoor is protected by three safety interlockswitches. Do not attempt to defeat them.
Under no circumstances should you try tooperate the oven with the door open.
• Proper operation of microwave ovens re-quires that the magnetron be properlyassembled to the waveguide and cavity.Never operate the magnetron unless it isproperly installed.
• Be sure the “RF” seal is not damaged andis assembled around the magnetron domeproperly when installing the magnetron.
• Routine service safety procedures shouldbe exercised at all times.
• Untrained personnel should not attemptservice without a thorough review of testprocedures and safety information con-tained in this Job Aid.
WARNING TO SERVICE TECHNICIANS
Whirlpool microwave ovens have a monitoringsystem designed to assure proper operation of the safety interlock systems.
The interlock monitor switch will immediately
cause the oven fuse to blow if the door isopened and the primary door interlock switchand/or the secondary interlock switch contactsfail in a closed position.
CAUTION: Replace a blown fuse with a 20ampere class H fuse only.
Test the upper and lower door interlockswitches, cook relay and interlock monitor switch (middle switch) for proper operation asdescribed in the component test procedures,
before replacing the blown oven fuse.Do not attempt to repair sticking contacts
of any interlock switch, safety switch, or Cook (Latch) relay. The components must
be replaced.
Any indication of sticking contacts during com-ponent tests requires replacement of that com-ponent to assure reliability of the safety inter-lock system.
If the fuse is blown, the Monitor, Primary,and Secondary interlock switches must bereplaced. Be sure they are properly con-nected.
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PRECAUTIONS TO BE OBSERVED BEFORE AND DURINGSERVICING TO AVOID POSSIBLE EXPOSURE
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 themagnetron or other microwave 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
Latches5)Evidence of Dropping or Abuse
C. Before turning on the microwave power for any service test or inspection within themicrowave generating components, check
the magnetron, wave guide or transmis-
sion line, and cavity for proper alignment,integrity, and connections.
D. Any defective or misadjusted componentsin the interlock, monitor, door seal, andmicrowave generation and transmissionsystems shall be repaired, replaced, or adjusted, using procedures described inthis Job Aid, before the oven is released tothe owner.
E. A microwave leakage check to verify com-pliance with Federal Performance Stan-
dard should be performed on each ovenprior to release to the owner.
F. Do not attempt to operate the oven if thedoor glass is broken.
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• Electromagnetic energy leakage monitor(NARDA 81 00B, HOLADAY H 1501 ).
• 275 ±15 ML glass beaker.
TEST
On every service call, checks for microwaveenergy emission must be made according tothe following manner.
1. Remove the cooking rack from the ovencavity, if the microwave oven is soequipped.
2. Place a 275 ±15 ML (9.3 oz.) glass ofwater in the center of the oven bottom.
3. Select "HIGH" cook power, turn the micro-wave oven on, and test for R.F. Ieakage atthe following locations:
a)Around the cabinet at the front.b)Around the door.c) Across the console panel.d)Horizontally across the door.e)Vertically across the door.f) Diagonally across the door.g)Across the air vents.h)Across the rear air vent.i) All lockseams.
j) Weld at bottom.k)Bottom plate.I) Oven feet.
4. The scan speed is one inch per second.
When checking for R.F. Ieakage, use an ap-proved R.F. measuring device to assure lessthan 4 mw/cm2 emission at 5 cm distance witha maximum scan rate of 2.54 cm/second, incompliance with U.S. Government Department
of Health, Education and Welfare 21CFR1030,performance Standard for Microwave Ovens.
A properly operating door and seal assemblywill normally register small emissions, but theymust be no greater than 4 mw/cm2 to allow for measurement uncertainty.
NOTE: Enter leakage readings in space BE-FORE and AFTER on the service document.
All microwave ovens exceeding the emissionlevel of 4 mw/cm2 must be reported to Dept. of
Service for microwave ovens immediately andthe owner should be told not to use the micro-wave oven until it has been repaired com-pletely.
If a microwave oven is found to operate with thedoor open, report to Dept. of Service, themanufacturer and CDRH* immediately. Alsotell the owner not to use the oven.
The interlock monitor switch acts as the finalsafety switch protecting the customer from
microwave radiation. If the interlock monitor switch operated to blow the fuse when theinterlocks failed, you must replace all interlockswitches with new ones, because the contactsof those interlock switches may be melted andwelded together.
If safety interlock/monitor switch replacement,or adjustment, is required, you must reconnectthe circuit, and perform a continuity check onthe monitor circuit.
All repairs must be performed in such a manner
that microwave energy emissions are minimal.
Address for CDRH is:
Office of Compliance (HFZ-342) Center for Devices and Radiological Health2098 Gaither RoadRockville, MD 20850
* CDRH: Center for Devices and Radiological Health,Food and Drug Administration.
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LIMITED FOUR-YEAR WAR-RANTY Secondthrough fifth yearfrom Date ofPurchase.
ONE-YEAR FULL
WARRANTYFrom Date ofPurchase.
LENGTH OFWARRANTY:
WHIRLPOOLWILL PAY FOR:
WHIRLPOOLWILL NOT PAY FOR:
WHIRLPOOL CORPORATION SHALL NOT BE LIABLE FOR INCIDENTAL OR CONSE-
QUENTIAL DAMAGES. Some states do not allow the exclusion or limitation of incidental or
consequential damages, so this exclusion or limitation may not apply to you. This warranty
gives you specific legal rights, and you may also have other rights which vary from state to
state.Outside the United States, this warranty does not apply. Contact your authorized Whirl-
pool dealer to determine if another warranty applies.
If you need service, see the “Requesting Assistance or Service” in the Use & Care Guide, or by
calling our Customer Interaction Center telephone number, 1-800-253-1301, from anywhere in
the U.S.A.
FSP ® Replace-
ment parts andrepair labor coststo correct defectsin materials orworkmanship.Service must beprovided by aWhirlpool-desig-nated servicingcompany.
FSP ® Replace-ment magnetrontube on microwaveovens if defectivein materials orworkmanship.
A. Service calls to:
1. Correct the installation of the microwaveoven.
2. Instruct you how to use the microwaveoven.
3. Replace house fuses or correct housewiring.
4. Replace owner-accessible light bulbs.
B. Repairs when microwave oven is used inother than normal single-family householduse.
C. In-home service. Your microwave oven mustbe taken to a Whirlpool-designated servicecompany, except when your microwave ovenis installed over an approved oven using anapproved built-in kit.
D. Damage to the microwave oven resultingfrom accident, alteration, misuse, abuse, fire,flood, acts of God, or use of products notapproved by Whirlpool Corporation.
E. Any labor costs during the limited warranty.
F. Repairs to parts or systems resulting from
unauthorized modifications made to theappliance.
G. Replacement parts or repair labor costs for units operated outside the United States.
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The vent motor capacitor is located in the highvoltage area of the oven and is accessed byremoving the control panel. It is in use any timethe vent motor is in operation. The capacitorhelps to maintain a constant voltage to the ventmotor so that it runs smoother and more effi-ciently.
The oven thermostat is located in the high volt-age section of the oven and is accessed byremoving the control panel. The thermostat isnormally-closed and will open at a set tempera-ture to disable the oven. The “trip” tempera-
ture is 194˚F (90˚C). The thermostat isresettable.
VENT MOTOR CAPACITOR
FUSE 20A
POWER
TRANS
OVEN THERMOSTAT
3 1
L N
RELAY 5
RELAY 7
VENT MOTOR
CAPACITOR
BK BK RD
BL
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COMPONENT ACCESSThis section instructs you on how to service each component inside the Model MH6140XKMicrowave Oven Hood Combination. The components and their locations are shown below.
Vent Motor
Cooktop Lamp
Turntable Motor
Primary Interlock Switch
High Voltage Rectifier
High Voltage Capacitor
Line Fuse
Magnetron
High VoltageTransformer
Oven Lamp
OvenThermostat
Vent Motor Capacitor
Monitor Switch
Secondary Interlock Switch
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REMOVING THE TURNTABLE MOTOR& COOKTOP LAMP ASSEMBLY
CAUTION: When you work on the microwaveoven, be careful when handling the sheet metalparts. Sharp edges may be present, and youcan cut yourself if you are not careful.
1. Disconnect the electrical power to themicrowave oven.
2. Remove the seven screws from the bot-tom cover and partially lower the top edgeof the cover so you can access the compo-nent wiring below it.
3. Lower the bottom cover as far as possible.
Bottom Cover
Screw (1 of 7)
Turntable Motor Connector
ELECTRICAL SHOCK HAZARDDisconnect power before servicing.
Replace all panels before operating.
Failure to do so could result in death or electrical shock.
WARNING4. To remove the turntable motor:
a) Remove the glass turntable, roller as-sembly, and spindle from inside the
oven cavity.
Spindle
Roller Assembly
GlassTurntable
b) Disconnect the turntable motor con-nector.
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CAUTION: When you work on the microwaveoven, be careful when handling the sheet metalparts. Sharp edges may be present, and youcan cut yourself if you are not careful.
5. Remove the screw from the top of thecontrol panel and pull the top forward.
1. Disconnect the electrical power to the
microwave oven.2. Remove the two outer screws from the top
of the cabinet.
3. Pull the top of the air grille forward, lift thebottom tabs from the slots, and removethe grille from the microwave oven.
Air Grille Screws
4. Open the microwave oven door.
6. Disconnect the 2- and 11-pin connectorsfrom the control board and remove thecontrol panel assembly.
Control Panel Screw
2-PinConnector
11-PinConnector
ControlPanel
Control PanelAssembly
ELECTRICAL SHOCK HAZARD
Disconnect power before servicing.Replace all panels before operating.
Failure to do so could result in death or electrical shock.
WARNING
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9. Remove the two screws from the trans-former bracket.
7. Place your fingertips under the ends of theribbon cable connector locking rail and liftthe rail, then pull the end of the ribboncable out of the connector.
Ground Wire Screw
LockingRail
8. Remove the green ground wire screwfrom the control panel.
Transformer Bracket Screws
10. Press the locking tab and unlock it fromthe end of the control board, then pull theother end of the board out of the holder slots, and remove the board.
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CAUTION: When you work on the microwaveoven, be careful when handling the sheet metalparts. Sharp edges may be present, and youcan cut yourself if you are not careful.
1. Disconnect the electrical power to the
microwave oven.2. Remove the control panel from the micro-
wave oven (see page 3-4 for the proce-dure).
3. To remove the primary interlock switch:
a) Disconnect the wire connectors fromthe terminals.
b) Carefully raise the locking arm, pull out,and remove the switch from the bracket.
4. To remove the monitor switch or sec-ondary interlock switch:
a) Disconnect the wire connectors fromthe terminals.
b) Carefully push in on the locking arm(be careful not to break it off) while youtwist the switch on the pivot pin, andremove the switch from the bracket.NOTE: If a locking arm breaks, you willhave to replace the entire bracket, sobe careful when bending the arms.
2 White Wires
2 White Wires(1 Large & 1 Small)
Raise Locking Arm
Pull Out Here
ELECTRICAL SHOCK HAZARD
Disconnect power before servicing.Replace all panels before operating.
Failure to do so could result in death or electrical shock.
WARNING
Monitor Switch
SecondaryInterlock Switch
Push Locking Arm
Push Locking Arm
Red
White & Yellow
Green
Yellow
PrimaryInterlock Switch
PrimaryInterlock Switch
Monitor Switch
SecondaryInterlock Switch
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CAUTION: When you work on the microwaveoven, be careful when handling the sheet metalparts. Sharp edges may be present, and youcan cut yourself if you are not careful.
1. Disconnect the electrical power to the
microwave oven.2. Remove the two outer screws from the top
of the cabinet.
3. Pull the top of the air grille forward, lift thebottom tabs from the slots, and removethe grille from the microwave oven.
Air Grille Screws
5. Facing the rear of the socket, turn it coun-terclockwise and align the socket lockingtabs with the bracket slots, and removethe socket.
4. Lift the oven lamp mounting bracket by itstab and remove the lamp assembly fromthe mounting location. NOTE: Be carefulnot to break the fragile wire socket con-nectors.
Lift Tab Lamp MountingBracket
6. Remove the bulb from the socket.
Unlock
Lock
Lamp Socket Slot
ELECTRICAL SHOCK HAZARD
Disconnect power before servicing.Replace all panels before operating.
Failure to do so could result in death or electrical shock.
WARNING
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REMOVING THE OVEN THERMOSTAT,LINE FUSE, & POWER CORD
CAUTION: When you work on the microwaveoven, be careful when handling the sheet metalparts. Sharp edges may be present, and youcan cut yourself if you are not careful.
1. Disconnect the electrical power to themicrowave oven.
2. Remove the control panel from the micro-wave oven (see page 3-4 for the proce-dure).
3. Remove the high voltage access panelfrom over the control panel opening.
5. To remove the line fuse:
a) Open the fuseholder.
b) Pull the clips off the ends of the 20Aline fuse and remove the fuse from thefuseholder.
ClipClip
20A Fuse
ELECTRICAL SHOCK HAZARDDisconnect power before servicing.
Replace all panels before operating.
Failure to do so could result in death or electrical shock.
WARNING
Power Cord
Oven Thermostat
Line Fuse
Oven Thermostat
4. To remove the oven thermostat:
a) Remove the wires from the terminals.
b) Position the terminals so they align with
the air cover slot and slide the thermo-stat out of the slot.
HVAccessPanel
Air Cover Slot
Fuseholder
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REMOVING THE VENT MOTOR CAPACITOR,THE HIGH VOLTAGE CAPACITOR & RECTIFIER
1. Disconnect the electrical power to themicrowave oven.
2. Remove the control panel from the micro-wave oven (see page 3-4 for the proce-dure).
3. Remove the high voltage access panelfrom over the control panel opening (seepage 3-8, step 3).
4. CAUTION: Discharge the high voltage
capacitor with a 20,000 Ω resistor to
chassis ground.
CAUTION: When you work on the microwaveoven, be careful when handling the sheet metalparts. Sharp edges may be present, and youcan cut yourself if you are not careful.
6. Splice the wires on the new capacitor tothe old capacitor wires.
7. To remove the high voltage capacitor
and high voltage rectifier:
a) Disconnect the wires and rectifier leadfrom the terminals of the high voltagecapacitor.
b) Remove the mounting screw from theclamp and remove the rectifier andcapacitor.
Vent Motor Capacitor
5. To remove the vent motor capacitor:
a) Cut the wires near the body of thecapacitor.
b) Unsnap the capacitor from the holder and lift it out of the holder.
Vent Motor Capacitor
ELECTRICAL SHOCK HAZARDDisconnect power before servicing.
Replace all panels before operating.
Failure to do so could result in death or electrical shock.
WARNING
HV Capacitor &HV Rectifier
HV Capacitor
Capacitor Clamp
Mounting ScrewHV Rectifier
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CAUTION: When you work on the microwaveoven, be careful when handling the sheet metalparts. Sharp edges may be present, and youcan cut yourself if you are not careful.
1. Disconnect the electrical power to the
microwave oven.2. Remove the control panel from the micro-
wave oven (see page 3-4 for the proce-dure).
3. Remove the high voltage access panelfrom over the control panel opening (seepage 3-8, step 3).
4. CAUTION: Discharge the high voltagecapacitor with a 20,000 Ω resistor to
chassis ground.
5. Remove the high voltage capacitor andhigh voltage rectifier (see page 3-10 for the procedure).
HV Transformer
6. Disconnect the white and black wires fromthe two terminals on the high voltage trans-former.
7. Disconnect the 3-wire connector from the
magnetron.
Black
White
3-Wire Connector
8. Remove the four screws from the highvoltage transformer (below the mountingplate) and remove the transformer.
Screw (1 of 4)
HV Transformer
ELECTRICAL SHOCK HAZARD
Disconnect power before servicing.Replace all panels before operating.
Failure to do so could result in death or electrical shock.
WARNING
4 Screws On Bottom Of Mounting Plate
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CAUTION: When you work on the microwaveoven, be careful when handling the sheet metalparts. Sharp edges may be present, and youcan cut yourself if you are not careful.
Magnetron
6. Remove the screw from the end of themounting bracket, lift the end of the bracket,and remove the magnetron from the unit.
Magnetron
Screw
ELECTRICAL SHOCK HAZARD
Disconnect power before servicing.Replace all panels before operating.
Failure to do so could result in death or electrical shock.
WARNING
1. Disconnect the electrical power to the
microwave oven.2. Remove the control panel from the micro-
wave oven (see page 3-4 for the proce-dure).
3. Remove the high voltage access panelfrom over the control panel opening (seepage 3-8, step 3).
4. CAUTION: Discharge the high voltage
capacitor with a 20,000 Ω resistor tochassis ground.
5. Remove the high voltage capacitor andhigh voltage rectifier (see page 3-10 for the procedure), and the high voltage trans-former (see page 3-11 for the procedure).
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Disconnect power before servicing.Replace all panels before operating.
Failure to do so could result in death or electrical shock.
REMOVING THE VENT MOTOR
1. Disconnect the electrical power to the
microwave oven.
2. Remove the glass turntable and roller assembly from inside the oven cavity.
CAUTION: When you work on the microwaveoven, be careful when handling the sheet metalparts. Sharp edges may be present, and youcan cut yourself if you are not careful.
WARNING
3. Remove the microwave oven from itsmounting location.
4. Remove the three screws from the air ventcover on the top of the cabinet and removethe cover.
Roller Assembly
GlassTurntable
5. Remove the vent motor mounting screwfrom the rear panel.
6. Lift the vent motor out of the opening at the
rear of the oven and disconnect the power connector from the main harness connec-tor.
Vent Motor Screw
Vent Motor Power Connector
Air Vent Cover 3 Screws
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REMOVING THE OVEN DOOR, THE SWITCHACTUATORS, AND THE OUTER GLASS
CAUTION: When you work on the microwaveoven, be careful when handling the sheet metalparts. Sharp edges may be present, and youcan cut yourself if you are not careful.
1. Disconnect the electrical power to themicrowave oven.
2. Open the microwave oven door and re-move the choke cover. To do this:
a) Use a small screwdriver and pry out onthe indicated corner of the choke cover until the bottom locking tab pops out.
Choke Cover
Pry Out With Small Screwdriver
3. To remove the oven door:
a) Lift the door and remove the bottomhinge pin from its bracket hole, thenlower the door and remove the tophinge pin from its bracket hole.
b) Use a putty knife and pry out along theinner edge of the choke cover.
c) Pull out on the cover to release all of the
locking tabs, and remove the cover from the door.
Pull OutPry Out Along Inner
Edge With Putty Knife
b) Place the door on a padded surfacewith the handle and outer glass facingdown.
Lower To Remove Top Hinge Pin
Lift To RemoveBottom Hinge Pin
ELECTRICAL SHOCK HAZARDDisconnect power before servicing.
Replace all panels before operating.
Failure to do so could result in death or electrical shock.
WARNING
Locking Tab
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d) Unhook the ends of the spring from theactuators.
4. To remove the switch actuators:
a) Remove the two inner door framescrews.
b) Start at the lower right corner of thedoor and unclip the locking tabs alongthe bottom and right sides of the inner door frame while you lift the frame.
c) When the inner door frame is free of thetabs, slide the frame out of the 3 topholders and remove it.
e) Unhook the actuators from the slots inthe inner door frame.
Door Frame Screw(1 of 2)
Inner Door Frame
Unclip 3 Tabs Start Here
Slide Out Of Holders
Unclip3 Tabs
Unhook Spring
Switch Actuators
Hook Hook
Continued on the next page.
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Refer to page 3-10 for the procedure for servic-ing the vent motor capacitor, page 3-8 for theline fuse and oven thermostat, and page 3-6 for the door switches.
1. Disconnect the electrical power to themicrowave oven.
2. Set the ohmmeter to the R x 1 scale.
3. To test the vent motor capacitor:
a) Disconnect the vent motor power con-nector from the main harness connec-tor.
b) Touch the ohmmeter leads to the mainharness connector with the yellow (pin6) and white (pin 3) wires. The meter should indicate several ohms andgradually return to infinity.
THE VENT MOTOR CAPACITOR, LINE FUSE,OVEN THERMOSTAT, & DOOR SWITCH
Oven Thermostat
Vent Motor Capacitor
white Yellow
Line Fuse
BlackBlack
White & Blue White
Door SwitchNormally-Open
Normally-Closed
5. To test the oven thermostat:
a) Disconnect the wires from the termi-nals.
b) Touch the ohmmeter leads to the ter-minals.
c) When the thermostat is open, (opens@ 194˚F / 90˚C), the meter will indi-cate infinity across the terminals.
d) When the thermostat is closed, themeter will indicate continuity.
6. To test the door switches:
a) Disconnect the wires from the termi-nals.
b) Touch the ohmmeter leads to the ter-minals of the primary or secondary
interlock switches (normally-open). The
meter should indicate an open circuit(infinite).
c) Touch the ohmmeter leads to the ter-minals of themonitor switch (normally-closed). The meter should indicate aclosed circuit (0 Ω).
NOTE: Pressing the actuator button shouldresult in opposite readings (normally-openshould read closed, and normally-closedshould read open).
4. To test the 20A line fuse, touch theohmmeter leads to the ends of the fuse.The meter should indicate continuity.
ELECTRICAL SHOCK HAZARDDisconnect power before servicing.
Replace all panels before operating.
Failure to do so could result in death or electrical shock.
WARNING
7/25/2019 8178053 Job Aid Microwave Oven Hood Combination
Refer to page 3-10 for the procedure for servic-ing the high voltage capacitor and rectifier.
1. Disconnect the electrical power to themicrowave oven.
2. Disconnect the rectifier and wire leadsfrom the high voltage capacitor.
3. To test the high voltage capacitor:
a) Set the ohmmeter to the R x 1K scale.
b) Touch the ohmmeter leads to the ca-pacitor terminals. The meter should in-dicate several ohms, and gradually re-turn to infinity.
c) Touch one ohmmeter lead to the ca-pacitor case. Touch the other lead toeach of the terminals. The meter shouldindicate infinity at both terminals.
THE HIGH VOLTAGE CAPACITOR & RECTIFIER (DIODE)
High Voltage Capacitor
High Voltage Rectifier
HV Transformer (wht)(+) Rectifier
Magnetron Filament (red-blk)
Anode Cathode
ELECTRICAL SHOCK HAZARD
Disconnect power before servicing.
Replace all panels before operating.
Failure to do so could result in death or electrical shock.
WARNING4. To test the high voltage rectifier:
a) Set the ohmmeter to the R x 1K scale.
b) Touch the positive ohmmeter lead tothe anode lead of the rectifier and thenegative ohmmeter lead to the cathodelead. The meter should indicate infin-ity.
c) Reverse the ohmmeter leads on therectifier and the meter should indicateinfinity.
NOTE: If the meter reads below 100Ω ineither direction, the rectifier is defectiveand should be replaced.
7/25/2019 8178053 Job Aid Microwave Oven Hood Combination
Refer to page 3-11 for the procedure for servic-ing the high voltage transformer.
1. Disconnect the electrical power to themicrowave oven.
2. Disconnect the high voltage transformer wires from the magnetron and high volt-age capacitor terminals.
3. Set the ohmmeter to the R x 1 scale.
4. Touch the ohmmeter leads to the twoprimary terminals. The meter should indi-cate less than 1 Ω.
5. Touch one ohmmeter lead to the whitesecondary wire terminal and the other lead to the transformer chassis groundlug. The meter should indicate between65 and 120 Ω.
6. Touch the ohmmeter leads to the two red-black filament terminals. The meter shouldindicate 0 Ω.
7. Set the ohmmeter to the R x 1K scale.
8. Touch one ohmmeter lead to the trans-former chassis ground lug. Touch the other lead to each of the filament terminals. Themeter should indicate infinity at both termi-nals.
THE HIGH VOLTAGE TRANSFORMER
Black
White
Red-Black
Red-Black
White
Filament Terminals
(Red-Black)
Secondary (White) To HV Capacitor
To HV Cap (Red-Blk)
Primary(Blk & Wht)
ELECTRICAL SHOCK HAZARD
Disconnect power before servicing.
Replace all panels before operating.
Failure to do so could result in death or electrical shock.
WARNINGHigh Voltage Transformer
7/25/2019 8178053 Job Aid Microwave Oven Hood Combination
Refer to page 3-12 for the procedure for servic-ing the magnetron.
1. Disconnect the electrical power to themicrowave oven.
2. Disconnect the wire connectors from thefilament terminals.
3. Set the ohmmeter to the R x 1 scale.
4 . Touch the ohmmeter leads to the filamentterminals. The meter should indicate lessthan 1 Ω.
5. Set the ohmmeter to the R x 1K scale.
6. Touch one ohmmeter lead to the magne-tron case. Touch the other lead to each of the filament terminals. The meter shouldindicate infinity at both terminals.
THE MAGNETRONMagnetron
Filament
Terminals
FilamentTerminals
ELECTRICAL SHOCK HAZARD
Disconnect power before servicing.
Replace all panels before operating.
Failure to do so could result in death or electrical shock.
WARNING
7/25/2019 8178053 Job Aid Microwave Oven Hood Combination