Jenn-Air JMD2124WS User manual

- ii -
Copyright © 2009, Whirlpool Corporation, Benton Harbor, MI 49022
FORWARD
This Jenn-Air, Drawer Microwave Oven job aid (Part No. 8178775), provides the technician with
information on the installation, operation, and service of the Drawer Microwave Oven. It is to
be used as a training Job Aid and Service Manual. For specic information on the model being
serviced, refer to the “Use and Care Guide,” or “Wiring Diagram” provided with the microwave
oven.
The Wiring Diagrams 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 servicing the unit.
GOALS AND OBJECTIVES
The goal of this Job Aid is to provide detailed information that will enable the service technician to
properly diagnose malfunctions and repair the KitchenAid Over-The-Counter Microwave Oven.
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 to its proper operational status.
WHIRLPOOL CORPORATION assumes no responsibility for any repairs made
on our products by anyone other than Authorized Service Technicians.

- iii -
TABLE OF CONTENTS
Page
GENERAL .............................................................................................................................. 1-1
Safety First......................................................................................................................... 1-1
Important Information for Service Technicians ................................................................... 1-4
Precautions To Be Observed Before And During Servicing
To Avoid Possible Exposure To Excessive Microwave Energy ........................................ 1-5
R.F. Leakage Test .............................................................................................................. 1-6
Model & Serial Number Label Location.............................................................................. 1-7
Specications..................................................................................................................... 1-8
Jenn-Air Cooking Appliance Warranty ............................................................................. 1-10
INSTALLATION REQUIREMENTS ........................................................................................ 2-1
Product Dimensions........................................................................................................... 2-2
THEORY OF OPERATION ..................................................................................................... 3-1
Microwave Operating Sequence........................................................................................ 3-1
The Absolute Humidity (AH) Sensor Circuit ....................................................................... 3-3
Schematic (Off Condition).................................................................................................. 3-5
COMPONENT ACCESS ........................................................................................................ 4-1
Component Locations ........................................................................................................ 4-1
Accessing Internal Components ........................................................................................ 4-2
Removing The Power Cord................................................................................................ 4-4
Removing The Secondary Interlock Switch, Monitor Switch And Front
And Rear Door Switch..................................................................................................... 4-5
Removing The Oven Lamp ................................................................................................ 4-7
Removing The Drawer Assembly....................................................................................... 4-8
Removing The Stirrer Cover And Stirrer Fan Assemblies .................................................. 4-9
Removing The Stirrer Motor............................................................................................. 4-10
Removing The Humidity Sensor .......................................................................................4-11
Interior Components Locations ........................................................................................ 4-12
Removing The High Voltage Capacitor And Diode .......................................................... 4-13
Removing The High Voltage Transformer ........................................................................ 4-14
Removing The Magnetron................................................................................................ 4-15
Removing The Cooling Fan Assembly ............................................................................. 4-16
Removing The Relay, Noise Filter And Power Supply Boards......................................... 4-17
Removing The Auto Drawer Gear .................................................................................... 4-18
Removing The Rack Gear................................................................................................ 4-19

- iv -
COMPONENT TESTING ........................................................................................................ 5-1
Microwave Oven Power Output Test.................................................................................. 5-1
Switching Power Supply (Switching Regulator) ................................................................. 5-3
Page
DIAGNOSIS & TROUBLESHOOTING .................................................................................. 6-1
Troubleshooting ................................................................................................................. 6-1
Primary Secondary And Monitor Interlock Switch Checkout Procedures........................... 6-2
Diagnostics......................................................................................................................... 6-3
WIRING DIAGRAM ................................................................................................................ 7-1
Schematic Diagram............................................................................................................ 7-1

1-1
This is the safety alert symbol.
This symbol alerts you to hazards that can kill or hurt you and others.
All safety messages will follow the safety alert symbol and either the word
“DANGER” or “WARNING.” These words mean:
GENERAL
Electrical Shock Hazard
Plug into a grounded 3-prong outlet.
Do not remove ground prong.
Do not use an adapter.
Do not use an extension cord.
Failure to follow these instructions can
result in death, re, or electrical shock.
Electrical Shock Hazard
Disconnect power before servicing.
Replace all parts and panels before
operating.
Failure to do so can result in death or
electrical shock.
SAFETY FIRST
Your safety and the safety of others is very important.
We have provided many important safety messages in this Job Aid and on the appliance.
Always read and obey all safety messages.
All safety messages will tell you what the potential hazard is, tell you how to reduce the
chance of injury, and tell you what can happen if the instructions are not followed.
You can be killed or seriously injured if
you don’t immediately follow instructions.
You can be killed or seriously injured if
you don’t follow instructions.
ELECTRICAL POWER SUPPLY &
GROUNDING REQUIREMENTS
WARNING
WARNING
WARNING
WARNING
WARNING
DANGER
WARNING
WARNING

1-2
Before touching any oven component or wiring,
always unplug the oven from its power source
and discharge the high voltage capacitor .
Check that the unit is grounded before trouble-
shooting. Be careful of the high voltage circuits.
Discharge any static charge from your body by
touching ground before handling any part of
the circuitry on the control board. Electrostatic
discharge may damage the control circuit.
Do not touch oven components or wiring dur-
ing operation. Attach meter leads with alligator
clips when making operational tests.
For continued protection against radiation emis-
sion, 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; Oven Lamp
Switch: SZM-V6-FA-31 or VP-331 A-OD.
It is neither necessary nor advisable to attempt
measurement of high voltage.
Attaching the adaptor ground terminal to the
wall receptacle cover screw does not ground
the appliance unless the cover screw is metal
and not insulated and the wall receptacle is
grounded through the house wiring.
The microwave oven must be grounded. In the
event of an electrical short circuit, grounding
reduces the risk of electrical shock by provid-
ing an escape wire for the electrical current.
The microwave oven is equipped with a cord
having a grounding wire with a grounding plug.
The plug must be plugged into an outlet that is
properly installed and grounded.
Consult a qualied electrician or serviceman if
the grounding instructions are not completely
understood, or if doubt exists as to whether
the microwave oven is properly grounded. Do
not use an extension cord. If the power supply
cord is too short, have a qualied electrician
or serviceman install an outlet near the micro-
wave oven.

1-3
ELECTROSTATIC DISCHARGE
(ESD) SENSITIVE ELECTRONICS
ESD problems are present everywhere. ESD
may damage or weaken the electronic control
assembly. The new control assembly may ap-
pear to work well after repair is nished, but
failure may occur at a later date due to ESD
stress.
• Use an antistatic wrist strap. Connect the
wrist strap to a green ground connection
point or unpainted metal in the appliance;
or touch your nger repeatedly to a green
ground connection point or unpainted metal
in the appliance.
• Before removing the part from its package,
touch the antistatic bag to a green ground
connection point or unpainted metal in the
appliance.
• Avoid touching electronic parts or terminal
contacts. Handle the electronic control as-
sembly by the edges only.
• When repackaging the failed electronic con-
trol assembly in an antistatic bag, observe
the above instructions.

1-4
To avoid possible exposure to microwave
radiation or energy, visually check the oven
for damage to the drawer and drawer seal
before operating any oven. Use a microwave
survey meter to check the amount of leakage
before servicing. In the event the R.F. Ieakage
exceeds 4 mw/cm2at 5 cm, appropriate repair
must be made before continuing to service the
unit. Check interlock function by operating the
drawer latch. The oven cook cycle should cut
off before the drawer can be opened.
The drawer and latching assembly contains the
radio frequency energy within the oven. The
drawer is protected by three safety interlock
switches. Do not attempt to defeat them.
Under no circumstances should you try to
operate the oven with the drawer open.
• Proper operation of microwave ovens
requires that the magnetron be properly
assembled to the waveguide and cavity.
Never operate the magnetron unless it is
properly installed.
• Be sure the “RF” seal is not damaged and
is assembled around the magnetron dome
properly when installing the magnetron.
• Routine service safety procedures should
be exercised at all times.
• Untrained personnel should not attempt
service without a thorough review of test
procedures and safety information con-
tained in this Job Aid.
IMPORTANT INFORMATION FOR SERVICE TECHNICIANS
Jenn-Air microwave ovens have a monitoring
system designed to assure proper operation
of the safety interlock systems.
The monitor switch will immediately cause the
oven fuse to blow if the drawer is opened and
the primary door interlock switch and/or the
secondary interlock switch contacts fail in a
closed position.
NOTE: Replace a blown fuse with a 20 am-
pere class H fuse only.
Test the upper and lower door interlock switch-
es, cook relay, and monitor switch (middle
switch) for proper operation as described 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
component tests requires replacement of that
component to assure reliability of the safety
interlock system.
If the fuse is blown, the Monitor switch,
and the Primary, and Secondary interlock
switches must be replaced. Be sure they
are properly connected.

1-5
PRECAUTIONS TO BE OBSERVED BEFORE AND DURING
SERVICING TO AVOID POSSIBLE EXPOSURE
TO EXCESSIVE MICROWAVE ENERGY
A. Do not operate or allow the oven to be
operated with the drawer open.
B. Make the following safety checks on all
ovens to be serviced before activating the
magnetron or other microwave source, and
make repairs as necessary:
1) Interlock Operation
2) Proper Drawer 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 the microwave power
for any service test or inspection within the
microwave generating components, check
the magnetron, wave guide or transmis-
sion line, and cavity for proper alignment,
integrity, and connections.
D. Any defective or misadjusted components
in the interlock, monitor, drawer seal, and
microwave generation and transmission
systems shall be repaired, replaced, or
adjusted, using procedures described in
this Job Aid, 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.
F. Do not attempt to operate the oven if the
drawer glass is broken.

1-6
R.F. LEAKAGE TEST
EQUIPMENT
• Electromagnetic energy leakage monitor
(NARDA 8100B, HOLADAY H 1501 ).
• 275 ±15 ML glass beaker.
TEST
On every service call, checks for microwave
energy emission must be made according to
the following manner.
1. Remove the cooking rack from the
oven cavity, if the microwave oven is so
equipped.
2. Place a 275 ±15 ML (9.3 oz.) glass of water
in the center of the oven bottom.
3. Select "HIGH" cook power, turn the micro-
wave oven on, and test for R.F. Ieakage
at the following locations:
a) Around the cabinet at the front.
b) Around the door/drawer.
c) Across the console panel.
d) Horizontally across the door/drawer.
e) Vertically across the door/drawer.
f) Diagonally across the door/drawer.
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 less
than 4 mw/cm2emission at 5 cm distance with
a maximum scan rate of 2.54 cm/second, in
compliance with U.S. Government Department
of Health, Education and Welfare 21CFR1030,
Performance Standard for Microwave Ovens.
Aproperly operating drawer and seal assembly
will normally register small emissions, but they
must be no greater than 4 mw/cm2to allow for
measurement uncertainty.
NOTE: Enter leakage readings in space BE-
FORE and AFTER on the service document.
All microwave ovens exceeding the emission
level of 4 mw/cm2must be reported to Dept.
of Service for Microwave Ovens immediately
and the owner should be told not to use the
micro- wave oven until it has been repaired
completely.
If a microwave oven is found to operate with
the door open, report to Dept. of Service, the
manufacturer and CDRH* immediately. Also
tell the owner not to use the oven.
The monitor switch acts as the nal safety
switch protecting the customer from microwave
radiation. If the monitor switch operated to blow
the fuse when the interlocks failed, you must
replace all interlock switches with new ones,
becausethecontactsof thoseinterlockswitches
may be melted and welded together.
If safety interlock/monitor switch replacement,
or adjustment, is required, you must reconnect
the circuit, and perform a continuity check on
the monitor circuit.
All repairs must be performed in such a man-
ner that microwave energy emissions are
minimal.
Address for CDRH is:
Ofce of Compliance (HFZ-312) Center for
Devices and Radiological Health
1390 Piccard Drive
Rockville, MD 20850
* CDRH: Center for Devices and Radiological