Thermador ME301J Series User manual

SERVICE MANUAL
for
Thermador Masterpiece
J-Series
Built-in Wall Ovens
Models:
ME301Jx, MED271JS, MED301Jx, ME302Jx,
MED272JS, MED302Jx, MEDMC301Jx,
MEDMCW71JS, MEDMCW31Jx
This manual contains information that is necessary for
servicing the following Thermador electric built-in wall
ovens:
ME301Jx, MED271JS, MED301Jx, ME302Jx,
MED272JS, MED302Jx, MEDMC301Jx,
MEDMCW71JS, MEDMCW31Jx
This manual is designed to be used by qualified
service personnel only. Due to the complexity and the
risk of high-voltage electrical shock, Thermador does
not recommend that customers service their own
units.
This material is intended for the sole use of BSH
authorized persons and may contain confidential and
proprietary information. Any unauthorized review, use,
copying, disclosure, or distribution in any format is
prohibited.

Service Manual for Thermador Masterpiece J-Series Built-in Wall Ovens 58300000170514 ARA EN B Page 2 of 37
Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
This material is intended for the sole use of BSH authorized persons and may contain confidential and proprietary information. Any unauthorized review, use, copying, disclosure, or distribution in any format is prohibited.
TABLE OF CONTENTS
1Symbols Used in this Manual...................................................3
2IMPORTANT SAFETY INFORMATION......................................4
2.1 Safety Before Servicing the Appliance..................................4
3General.......................................................................................6
3.1 Models .................................................................................6
3.2 Features and Options...........................................................6
3.3 Data Plate ............................................................................8
3.4 Warranty...............................................................................8
4Operation ...................................................................................8
4.1 Element Duty Cycles ............................................................8
4.1.1 Using Table 4 (Element Duty Cycles During Preheat) ...9
4.2 Sequence of Events .............................................................9
4.3 Cooling Fan........................................................................11
5Component Accessibility........................................................11
5.1 Serviceable from Front.......................................................11
5.2 Serviceable from Top .........................................................11
5.3 Serviceable from Rear........................................................11
6Service and Repair..................................................................12
6.1 Doors .................................................................................12
6.1.1 Removing and Replacing the Door(s)..........................12
6.2 Hinges................................................................................13
6.3 Door Latch/Motor Assembly ...............................................14
6.3.1 Stuck Latch .................................................................14
6.3.2 Replacing the Latch/Motor Assembly ..........................14
6.4 Lighting / Lamps.................................................................14
6.4.1 Operation ....................................................................14
6.4.2 Bulb Specifications......................................................14
6.4.3 Replacing Bulbs ..........................................................15
6.5 High Temperature Cutout (HTC).........................................15
6.6 Convection Fan and Ring Element.....................................15
6.7 Temperature Sensor...........................................................16
6.7.1 Setting Temperature Offsets........................................16
6.8 Broil Element......................................................................17
6.9 User Interface.....................................................................17
6.10 PC Control Module (Relay Board) ......................................17
6.11 Power Supply Module.........................................................20
6.12 Convection Fan Motor........................................................21
6.13 Bake Element (Upper Oven) ..............................................21
6.13.1 Removing the Bake Element.......................................21
6.13.2 Reinstalling the Bake Element.....................................21
6.14 Cooling Fan Motor (Upper Oven) .......................................21
7Error Codes .............................................................................22
7.1 Error Code Table................................................................22
7.2 Service Mode / Setting Option Code ..................................23
7.2.1 Option Codes..............................................................23
7.2.2 Entering Service Mode................................................23
7.2.3 Setting Option Code....................................................24
7.2.4 Exiting Service Mode...................................................24
7.2.5 Resetting the Oven .....................................................24
8Demo Mode..............................................................................24
9Troubleshooting......................................................................24
9.1 Fault Tree Diagram ............................................................25
9.2 Fault Tree...........................................................................27
9.3 Testing...............................................................................35
10 Wiring Diagrams and Schematics..........................................35
10.1 Wire Color Key...................................................................35
10.2 Strip Diagrams ...................................................................36
11 Additional References.............................................................36
11.1 QuickFinder........................................................................36
11.2 Technical Support ..............................................................36

Service Manual for Thermador Masterpiece J-Series Built-in Wall Ovens 58300000170514 ARA EN B Page 3 of 37
Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
This material is intended for the sole use of BSH authorized persons and may contain confidential and proprietary information. Any unauthorized review, use, copying, disclosure, or distribution in any format is prohibited.
1 SYMBOLS USED IN THIS MANUAL
WARNING – this symbol alerts you to dangers that may
result in bodily injury or death
CAUTION – this symbol alerts you to actions that may
result in damage to the product or property

NOTICE – this symbol alerts you to important information
and/or service tips.
VIDEO – related service video available for viewing on
QuickFinder
!
!

Service Manual for Thermador Masterpiece J-Series Built-in Wall Ovens 58300000170514 ARA EN B Page 4 of 37
Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
This material is intended for the sole use of BSH authorized persons and may contain confidential and proprietary information. Any unauthorized review, use, copying, disclosure, or distribution in any format is prohibited.
2 IMPORTANT SAFETY INFORMATION
Before starting to service an appliance, familiarize yourself with all
safety information and precautions included in this manual.
2.1 Safety Before Servicing the Appliance
WARNING
Before disassembly, removal, or installation of any
component…
Turn off electrical power by removing the power cord from
the electrical outlet or putting the circuit breaker in the OFF
position.
Be sure the entire appliance has cooled to a safe
temperature.
!
WARNING
Use of replacement parts…
Use only authorized replacement parts for this appliance. Use of
unauthorized substitutions may cause non-compliance with safety
standards set for home appliances, will void the warranty, and may
create safety hazards resulting in damage, bodily injury, or death.
!
WARNING
Electrical hazards…
Before servicing the appliance, remove electrical power by
either disconnecting the power cord from the wall receptacle
or by putting the circuit breaker in the OFF position.
If tests must be conducted while the appliance is live, always
use a residual-current-operated circuit breaker. The
protective conductor connection must not exceed the
recommended values.
When repairs are complete, perform a function test in
accordance with the appropriate regulations.
Do not, under any circumstances, cut or remove the separate
ground wire or the third (ground) prong from the power cord
plug.
Improper grounding or reverse polarization will cause
malfunction, which can damage the appliance and create an
electrical shock hazard. Make sure the circuit is properly
grounded and polarized in accordance with applicable local
codes and ordinances. Receptacle replacement shall be in
accordance with the National Electric Code.
!
WARNING
Sharp components…
This appliance has sheet metal parts and components which may
have sharp edges. Avoid injury by handling parts with care and using
adequate protective measures, such as wearing gloves.
!

Service Manual for Thermador Masterpiece J-Series Built-in Wall Ovens 58300000170514 ARA EN B Page 5 of 37
Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
This material is intended for the sole use of BSH authorized persons and may contain confidential and proprietary information. Any unauthorized review, use, copying, disclosure, or distribution in any format is prohibited.
WARNING
Clean-up hazards…
Do not allow any cleaning or polishing solutions/compounds,
disinfectants, or bleaches to remain in contact with the stainless steel
surfaces for long periods, or after clean-up. These may contain
chemicals or materials which could release harmful inhalants and
may cause damage to the appliance. After cleaning or polishing,
always rinse the cleaning/polishing materials with clear water and
wipe dry with a clean, soft, non-abrasive cloth.
!
WARNING
Prior to returning appliance to service, confirm that…
All electrical connections are correct and secure
All safety grounds (internal and external) are correctly and
securely connected
All panels and components are properly and securely
reassembled.
!

Service Manual for Thermador Masterpiece J-Series Built-in Wall Ovens 58300000170514 ARA EN B Page 6 of 37
Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
This material is intended for the sole use of BSH authorized persons and may contain confidential and proprietary information. Any unauthorized review, use, copying, disclosure, or distribution in any format is prohibited.
Table 1 Model configuration
3 GENERAL
There are 15 ME/MED models in various combinations included in the
Thermador Masterpiece Built-in Wall Oven (BIWO) J-Series. These
models utilize true convection and thermal oven cavities. The
combination models include a built-in variation of the WD27JS or
WD30Jx warming drawer and/or a convection (MCEx) microwave.
All models have a glass and stainless user interface (touch panel)
with light blue graphical LCD displays. Fast preheat capability, 2-hour
self-clean, telescopic racks, and Star-K Certification are among the
features offered.
Grade 304 stainless steel is used on the control panel trim and door
skin on all models.
Models ending in JP have Pro handles; JS models have Masterpiece
handles.
3.1 Models
The table below describes the configuration of each SKU.
27”
O
VENS
MED271JS
Single oven with true convection
MED272JS
Double oven with true convection (both cavities)
MEDMCW71JS Triple combination with true convection oven, convection
microwave, and traditional warming drawer
30”
O
VENS
ME301Jx
Single oven with true convection
ME302Jx
Double oven with true convection (upper) and thermal (lower)
MED301Jx
Single oven with true convection
MED302Jx
Double oven with true convection (both cavities)
MEDMC301Jx Double combination with true convection oven and convection
microwave
MEDMCW31Jx Triple combination with true convection oven, convection
microwave, and traditional warming drawer
3.2 Features and Options
Tables 2 and 3 reflect the cooking modes and features of each model.
Table 2Cooking modes and features (27” models)

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Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
This material is intended for the sole use of BSH authorized persons and may contain confidential and proprietary information. Any unauthorized review, use, copying, disclosure, or distribution in any format is prohibited.
Table 3Cooking modes and features (30” models)

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Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
This material is intended for the sole use of BSH authorized persons and may contain confidential and proprietary information. Any unauthorized review, use, copying, disclosure, or distribution in any format is prohibited.
3.3 Data Plate
The data plate reflecting model number and FD number is located on
the underside of the interface control panel, as shown in Figure 1.
The first 4 positions of the FD number reflect the year/month the
product was produced. FD numbers that begin with 92 were built in
2012; 93 = 2013; 94 = 2014, etc.
3.4 Warranty
The product is warranted to be free from defects in materials and
workmanship for a period of 24 months from date of purchase.
Thermador will pay for all repair labor and replacement parts found to
be defective due to materials and workmanship. Service must be
provided by a Factory Authorized Service Agency, during normal
working hours.
Thermador assumes no responsibility for any repairs made on our
products by anyone other than authorized service technicians.
Find the complete product warranty statement in the Use and Care
Guide.
4 OPERATION
4.1 Element Duty Cycles
A PID algorithm controls the way in which the elements cycle on and
off during each cooking mode duty cycle. Every minute, the oven
temperature is compared to the set point and a recalculation occurs,
which results in varied element cycle times rather than the standard
fixed 60-second cycle.
During Preheat, however, a 2-point control is still used and there is a
defined element on-time. Table 4 reflects the duration and start point
by Preheat mode, for cavity types A, B, and C.
Technicians should have ample time to troubleshoot element
problems during the ~10-minute preheat period.
Figure 1 Data plate
NOTICE
Be prepared to provide the complete model number and FD
number on the data tag of the unit when contacting Thermador
Customer Support or Technical Support for assistance.

Service Manual for Thermador Masterpiece J-Series Built-in Wall Ovens 58300000170514 ARA EN B Page 9 of 37
Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
This material is intended for the sole use of BSH authorized persons and may contain confidential and proprietary information. Any unauthorized review, use, copying, disclosure, or distribution in any format is prohibited.
4.1.1 Using Table 4 (Element Duty Cycles During Preheat)
In Table 4, Duration is defined as the number of seconds an element
is turned on (e.g., 12 indicates the element will be on for 12 seconds.)
Start Point is defined as the point in the cycle at which the element will
turn on (e.g., 30 indicates the element will turn on in the 30th second
of the cycle).
Using the data in the table, below is an example of how the elements
cycle on and off during a 60-second Preheat cycle in True
Convection mode:
•Bake Element: After initial 33 seconds of the cycle, element
turns on and remains on for the final 27 seconds of the cycle.
•Ring Element: After initial 36 seconds of the cycle, element
turns on and remains on for the final 24 seconds of the cycle.
•Broil Element: Turns on at the beginning of the cycle (0) and
remains on for the first 27 seconds of the cycle.
In Fast Preheat (available in cavities B and C with convection fan), the
same elements reflected in the table are used, but the broil element is
on ~10% longer, and the convection fan stays on as well.
It is important to note that during regulation (regular cooking period
that follows Preheat), different elements may be used and element
duty cycles will vary.
4.2 Sequence of Events
Figures 2 – 5 reflect the sequence of events which occur during
Preheat for the various cooking modes.
Figure 2 Sequence of Events during Preheat: Convection Bake & Roast/ Bake,
Roast, Warm, Proof, Pizza, Pie, & Sabbath modes
Table 4 Element duty cycles during preheat by cavity type.

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Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
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Figure 3 Sequence of Events during Preheat: Convection Broil/Broil modes
Figure 4 Sequence of Events during Preheat: True Convection

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Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
This material is intended for the sole use of BSH authorized persons and may contain confidential and proprietary information. Any unauthorized review, use, copying, disclosure, or distribution in any format is prohibited.
Figure 5 Sequence of Events during Preheat: Self-clean mode
4.3 Cooling Fan
The cooling fan will run for two minutes after the oven has been shut
off, regardless of the oven temperature. After two minutes, the fan will
continue to run until the interior temperature of the cavity reaches a
maximum of 350°.
During self-clean, the fan will run continuously as long as the door
remains locked.
5 COMPONENT ACCESSIBILITY
5.1 Serviceable from Front
Door
Door latch/motor assembly
Cavity lamps
High Temperature Cutout (HTC)
Convection ring element and convection fan assembly (except
motor)
Temperature sensor
Broil element
The User Interface is serviceable from the front after sliding the oven
out from the wall ~ 4 inches.
5.2 Serviceable from Top
The PC control module (relay board) is serviceable from the top
access panel after sliding the oven out from the wall ~16 inches.
With the unit pulled completely away from the wall, the following
components are serviceable from the top after removing the top
panel:
Terminal block
Power supply
5.3 Serviceable from Rear
With the unit pulled completely away from the wall and the back
panel(s) removed, the following components can be serviced from the
rear:
Convection fan motor
Bake element
Cooling fan(s)

Service Manual for Thermador Masterpiece J-Series Built-in Wall Ovens 58300000170514 ARA EN B Page 12 of 37
Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
This material is intended for the sole use of BSH authorized persons and may contain confidential and proprietary information. Any unauthorized review, use, copying, disclosure, or distribution in any format is prohibited.
6 SERVICE AND REPAIR
6.1 Doors
On double ovens, the Thermador logo is located on the upper oven
outer door glass.
The Masterpiece Series handles are interchangeable with the
Professional Series handles.
6.1.1 Removing and Replacing the Door(s)
SoftClose hinges are used on the oven doors to prevent slamming
and ensure smooth operation. Before removing the door, it is
necessary to remove a hinge locking plate and open the hinge locking
lever on each side of the door in order to remove tension from the
hinge springs.
Removing the Door
1. Open door fully until parallel to the floor.
2. Remove T20 screw securing hinge locking plate (A); lift locking
plate upwards, then pivot outward to remove (B). Repeat on
other side of door, and retain the screws and locking plates.
3. Flip the RH and LH locking levers toward the top of the door
as far as they will go. (A flat blade screwdriver may be used to
open the levers.)
CAUTION
Avoid injury when removing and replacing oven doors.
Be sure oven is cool enough for handling and power is turned off.
Avoid injury from hinge bracket snapping closed; both locking
levers must be securely in place before removing door.
Use both hands and grasp door only by sides, not by the handle.
Do not force door open or closed.
Handle with care–door weighs over pounds.
Lay door on flat, smooth surface protected by a blanket or
cushion, positioned so that door will not fall over.
CAUTION
Sheet metal parts often have sharp edges. Avoid injury by
handling these parts with care.
Turn off the electrical power circuit to the oven at the main junction
box before servicing this unit.
For those checks requiring the use of electrical power, exercise
extreme care.
Figure 6 Removing the RH hinge locking plate
A
B
Figure 7Opening the RH hinge locking lever

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Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
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4. Confirm that the locking levers are locked in the open position
(toward the top of the door), then carefully close the door until
the top edge of the door is approximately 5 ½“ from the bottom
edge of the control panel (~30° angle).
5. Use both hands to grasp the door firmly on both sides, and lift
upward and outward at an angle so that the hinge foot on each
side will disengage from the hinge slots in oven chassis.
6. Carefully lay door on flat, smooth surface protected by a
blanket or cushion.
Reinstalling the Door
1. Grasp door firmly in both hands, holding at a 30° angle in front
of the oven, then guide the hinge feet into the hinge slots on
each side of oven chassis. If necessary, rock door slightly to
properly engage the hinges.
2. Carefully lower the door into a fully open position; if door will
not open to 90°, hinges are not correctly seated in slots and
step 1 should be repeated.
3. Push the right and left locking levers forward toward oven
cavity.
4. Reinstall right and left locking plates using the T20 screws.
5. Hold the door firmly and gently close to check operation. Be
aware that the door may slam shut if the door has been left in
a horizontal position for 4 hours or more and the dampening oil
in the hinge cylinders has not had sufficient time to flow to the
bottom of the cylinders (see section 6.2 Hinges for additional
information).
6. Open and close the door several times to ensure that door is
correctly installed; door must close smoothly, and fit squarely
and securely.
6.2 Hinges
SoftClose hinges are used on the J-series ovens. Each hinge has a
cylinder inside which holds oil that acts as a dampening fluid and
causes the soft-close effect. For the hinge to dampen properly, the oil
must be in the bottom of the cylinder. If doors or replacement hinges
have been in a horizontal position for 4 hours or more, or stored in a
very cold location, the hinges may temporarily lose the ability to
dampen as expected.
After replacing both hinges and/or re-installing the oven door, carefully
close the door to test its operation. Be aware that the door may slam
shut if the oil has not had sufficient time to flow to the bottom of the
hinge cylinders.
If the door does not close softly, open and close the door few times,
then allow the hinges time to recover in the vertical position (with door
closed). The expected recovery time for hinges which have been
stored or shipped horizontally is approximately 15-30 minutes. Hinges
that are very cold take longer to recover.
After 15-20 minutes, test the operation of the door again to ensure
that the hinges have begun to dampen. Note that it may take a few
more minutes until the hinges have completely recovered and are
operating with full dampening.
Figure 8Removing the door

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Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
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Hinges should always be replaced in pairs to ensure optimal operation
of the door.
6.3 Door Latch/Motor Assembly
The motorized door latch (MDL) mechanism (120V 5W) has 2
switches - the door switch and the lock/unlock switch. The latch will
automatically lock when mode and temperature selectors are set to
CLEAN, and unlock when the oven cools to ~490°F. It is serviced as
an assembly.
Two different motorized latches have been used in the J-series ovens,
and each has a slightly different design. See Figures 9 and 10.
The latch can be tested in Service Mode.
6.3.1 Stuck Latch
If the latch becomes stuck in the locked position, turning the unit off
and back on will normally open the latch if the cavity temperature
<450°. If latch is stuck in partially locked position, press SELF CLEAN,
then ON/OFF. If these measures fail, run a thin wire or wire coat
hanger in between the door and the front face of the oven. Figures 9
and 10 show the position of the wire between the latch hook (1) and
the plunger (2). Slide the wire to the left, pushing the latch hook left
and releasing the latch.
6.3.2 Replacing the Latch/Motor Assembly
Refer to QuickFinder bulletin linked to Latch Service Kit 751505.
6.4 Lighting / Lamps
All Masterpiece J-series ovens have three halogen lamps per cavity:
one rectangular-shaped lamp on the side of the cavity, and two round
lamps on the cavity ceiling. The same 120V/25W/G9-base halogen
bulb is used in all lamp receptacles. Replacement bulbs may be
purchased at local retail stores.
All MEDx models feature theater-style lighting, which progressively
brightens and dims.
If the lights are not functioning properly, enter Service Mode and verify
that the Option Code is correctly set. See section 7.2 Service
Mode/Setting Option Code for additional information.
6.4.1 Operation
On double ovens, if the OVEN LIGHT button is pressed without first
pressing UPPER or LOWER, the lights in both cavities will turn on. If
UPPER or LOWER is pressed first, only the lights in the selected cavity
will turn on.
The lights will automatically illuminate whenever the oven door is
opened, and turn off when the door is closed.
6.4.2 Bulb Specifications
The same 120V/25W/G9-base halogen bulb is used in all lamp
receptacles. Replacement bulbs may be purchased at local retail
stores.
Figure 10 Subsequent latch in locked position
2
1
Figure 9 Original latch in locked position
2
1
Figure 11 Halogen bulb

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Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
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The glass lamp covers protect the bulbs and must be in place when
using the appliance.
6.4.3 Replacing Bulbs
Halogen bulbs must be handled with a clean, dry cloth.
6.4.3.1 Rectangular-Shaped Side Lamp
1. Disconnect power to the oven.
2. Remove oven racks (if necessary) to allow access to the lamp
cover and bulb. (Door may be removed for easier access and
better visibility; refer to section 6.1 Doors.)
3. Insert tip of a narrow flat blade screwdriver between the metal
clips at a 40° angle.
4. While supporting the glass lamp cover, push the screwdriver
blade inward to disengage the catch from the slot in the light
housing.
5. Gently pry the cover off; it should detach easily – do not force.
6. Pull halogen bulb from socket.
7. Grasp new bulb with clean, dry cloth.
8. Align prongs with socket holes and press into place.
9. Insert glass lamp cover into mounting clip and press the end
nearest the front of the oven until it locks into place.
10. Restore power and test.
6.4.3.2 Round Lamps
1. Disconnect power to the oven.
2. Remove oven racks (if necessary) to allow access to the lamp
lens and bulb. (Door may be removed for easier access and
better visibility; refer to section 6.1 Doors.)
3. Remove glass lamp cover by turning it counter-clockwise.
4. Remove bulb by pulling it straight down out of the receptacle.
5. Grasp new bulb with clean, dry cloth.
6. Align prongs with socket holes and press into place.
7. Reinstall the glass lamp cover.
8. Restore power and test.
6.5 High Temperature Cutout (HTC)
The HTC is a normally closed switch which will interrupt the relay
supply voltage in the event of a high-temperature event caused by a
malfunctioning control module.
The HTC is located in the plenum, behind and to the left of the MDL.
Although it cannot be easily removed or replaced, a screwdriver can
be used to reach the reset button located on the top center of the HTC
after the latch plate has been removed.
6.6 Convection Fan and Ring Element
All models in the Masterpiece Series are configured with true
convection capabilities in one or more oven cavities. The ME302Jx
CAUTION

Turn off power to the oven at the fuse or breaker box–light
socket is live with door open.
Be sure oven and lights are cool to the touch.
Handle glass lenses with care.
Figure 12Removing rectangular lamp cover

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Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
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Table 5 Normal temperature sensor resistance readings
models have true European convection (both a convection fan and a
convection element) in the upper oven and thermal convection in the
lower oven. MED models have true convection in all cavities.
Depending on the cooking mode selected, the fan may be used, with
or without the ring element, to circulate heat evenly throughout the
cavity in various cooking modes.
The ring element (240V 2000W) and/or fan blade are easily accessed
on the rear wall of the oven cavity behind the convection baffle. The
convection fan motor is accessible only from the rear of the unit.
Refer to the Element Strip Diagram to test the element at the control
module, or:
1. Remove 2 T20 screws on either side of the element terminals.
2. Pull the element toward you so that terminal wires are inside
the oven cavity.
3. Disconnect the wires from the terminals.
4. Use an ohmmeter to check for resistance of ~29 ohms.
6.7 Temperature Sensor
Use an ohmmeter to check the resistance of the sensor. Normal
ranges (based on cavity temperature) are shown in Table 5.
Real-time cavity and probe temperatures can be measured while in
Service Mode (refer to the section entitled Service Mode or the
Service Guide for instructions). After entering Service Mode, advance
through the menu options by pressing FAST PREHEAT until the
Temperatures option is reached.
6.7.1 Setting Temperature Offsets
In some cases, it may be necessary to adjust the oven temperature if
food is consistently under- or over-cooked. Temperature offsets can
be entered from the User Settings menu to raise or lower the cavity
temperature during Bake, Convection Bake, Roast, Convection Roast,
and Speed Convection modes (all heating modes which operate
between 250°F and 550°F). To access the User Settings menu…
1. Press INFO; the main User Settings menu will appear
2. Select 2for Custom; the initial list of options will appear
3. Select 4for More; repeat.
4. Select 3for Temp Offset.
5. Select 1Upper or 2 Lower oven.

Service Manual for Thermador Masterpiece J-Series Built-in Wall Ovens 58300000170514 ARA EN B Page 17 of 37
Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
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6. Select 1- if you wish to lower the oven temperature by the
offset amount or 2+if you wish to raise the oven temperature
by the offset amount.
7. Using the numeric keypad, enter the desired offset amount.
8. Press BACK.
9. Select 1for Back without changes or 2Back with changes.
10. Press INFO to exit user settings.
•To view the offset, repeat steps 1 – 6.
•To revert back to default settings, press INFO, then select 2for
Standard.
•To change the offset, first revert back to default settings, then
repeat steps 1 – 10.
A +25° offset will result in a cavity temperature of 350° when the
temperature knob is set to 325° for any of the cooking modes listed
above. Similarly, a -25° offset will result in a cavity temperature of
300° when the temperature knob is set to 325°.
The adjusted temperature cannot be less than 250°F or greater than
550°F.
6.8 Broil Element
All single oven models, as well as the upper cavity of double oven
models, have a 10-pass (240V 3600W) broil element.
Refer to the Element Strip Diagram to test the element at the control
module, or:
1. Remove the 2 T20 screws securing the element to the broil
reflector.
2. Remove the 2 T20 screws on either side of the element
terminals.
3. Pull the element toward you so that the terminal wires are
inside the oven cavity.
4. Disconnect the wires from the inner broil element terminals.
5. Use an ohmmeter to check for resistance of ~16 ohms.
6.9 User Interface
Figure 13 reflects the 3 variations of the T1 user interface used in the
Masterpiece Series ovens.
The user interface control board is assembled onto a chassis and the
entire assembly is serviced as a single unit.
After replacing the user interface board, always confirm that the option
code is set correctly, reset the oven, and test operation. See section
7.2 Service Mode/Setting Option Code for additional information.
6.10 PC Control Module (Relay Board)
To access the PC control module, pull the unit out from the wall 15-16
inches, and remove the access panel (3 T20 screws) on the top of the
unit. See Figure 14.
Figure 13T1 User Interface variations
ME models (T1S1)
MED Single/combo
models (T1S2)
MED Double models
(T1D)

Service Manual for Thermador Masterpiece J-Series Built-in Wall Ovens 58300000170514 ARA EN B Page 18 of 37
Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
This material is intended for the sole use of BSH authorized persons and may contain confidential and proprietary information. Any unauthorized review, use, copying, disclosure, or distribution in any format is prohibited.
Figure 16 Relay locations on the double oven control module
Whenever possible, conduct troubleshooting tests at the control
module. Refer to Figures 15 and 16 for plug and relay locations.
After replacing the control module, always confirm that the option
code is set correctly, reset the oven, and test operation. See section
7.2 Service Mode/Setting Option Code for additional information.
Use Table 6 as a reference guide to the plugs, pins, and wire colors
found on the PC control module.
PLUG NO
PIN NO
FROM/TO
COMMUNICATION
X1
5-position card-edge
connector - WH
Control Module to Power Supply Module
X2
3-position card-edge
connector - YE
Control Module to User Interface Module
X3
3-position card-edge
Control Module to Factory Service Port
NOTICE
More than 75% of the control modules returned to the factory are fully
functional. Before diagnosing a bad control module, be sure to
disconnect and reconnect each wire/wire harness.
Figure 14PC Control Module is visible after removing access panel.
Figure 15 Plug locations on the double oven control module
X101
X102
X107
X103
X104
X105
X106
X1
X2
X3
X20
X21
X11
X204
X203
X202
X201
X205
X206
X207
Rear
Front

Service Manual for Thermador Masterpiece J-Series Built-in Wall Ovens 58300000170514 ARA EN B Page 19 of 37
Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
This material is intended for the sole use of BSH authorized persons and may contain confidential and proprietary information. Any unauthorized review, use, copying, disclosure, or distribution in any format is prohibited.
PLUG NO
PIN NO
FROM/TO
connector - YE
X108* 2-position card-edge
connector - WH/GN
Control Module to Meat Probe
UPPER/SINGLE CAVITY ELEMENTS
X101 1-OR K102 Relay to Bake Element
2-BK
L1 to K102 Relay
3-Blank N/A
4-BK
L1 to K104 Relay
5-Blank
N/A
6-BU K104 Relay to Ring Element
X102
1-YE
K003 DLB Relay to Inner Broil Element
2-Not Used N/A
3-Blank
N/A
4-RD
L2 to K003 DLB Relay
5-RD L2 to K003 DLB Relay
X103
1-BU
K002 DLB Relay to Ring Element
2-RD L2 to K002 DLB Relay
3-Blank
N/A
4-RD
L2 to K001 DLB Relay
5-Blank N/A
6-OR
K001 DLB Relay to Bake Element
7-Blank N/A
X104
1-Blank
N/A
2-Blank
N/A
3-Blank N/A
4-BK
L1 to K106 Relay
5-BK L1 to K106 Relay
6-Blank
N/A
7-Not Used
N/A
8-YE K106 Relay to Broil Element
X110
1-BU
High Temperature Cutout (HTC)
2-Not Used N/A
3-BU
High Temperature Cutout (HTC)
PLUG NO
PIN NO
FROM/TO
UPPER/SINGLE CAVITY SMALL LOAD
X105 1-Blank N/A
2-YE
K112 Relay to Convection Fan
3-BU/WH K114 Relay to Cooling Fan (L)
4-BU
K115 Relay to Cooling Fan (H)
5-BN
K115 to Light Transformer
6-Blank N/A
7-BN
K117 Relay to Motorized Door Latch (MDL)
8-RD L2 to K117 Relay
X106
1-YE
Door Switch
2-YE
Door Switch
3-Not Used N/A
4-YE/BK
Latch Switch
5-OR/BK Latch Switch
6-VT/WH
Door Switch
7-BN/WH
Door Switch
X107 1-WH Hall Effect Sensor
2-BK
Hall Effect Sensor
3-RD Hall Effect Sensor
4-WH
Temperature Sensor
5-WH
Temperature Sensor
X110 1-BU High Temperature Cutout (HTC)
2-Not Used
N/A
3-BU High Temperature Cutout (HTC)
LOWER CAVITY ELEMENTS
X201 1-BU ** K204 Relay to Ring Element
2-Blank
N/A
3-Blank N/A
4-BK **
L1 to K204 Relay
5-BK
L1 to K202 Relay
6-Blank N/A
7-OR
K202 Relay to Bake Element

Service Manual for Thermador Masterpiece J-Series Built-in Wall Ovens 58300000170514 ARA EN B Page 20 of 37
Copyright by BSH Home Appliances Corporation (Revised May 2013) 1901 Main Street, Suite 600, Irvine CA 800 444-9091
This material is intended for the sole use of BSH authorized persons and may contain confidential and proprietary information. Any unauthorized review, use, copying, disclosure, or distribution in any format is prohibited.
PLUG NO
PIN NO
FROM/TO
X202
1-RD
L2
2-RD
L2 to K006 DLB Relay
3-Not Used N/A
4-Not Used
N/A
5-YE K006 DLB Relay to Broil Element
X203
1-OR
K004 DLB Relay to Bake Element
2-Not Used
N/A
3-RD L2 to K004 DLB Relay
4-Blank
N/A
5-RD ** L2 to K005 DLB Relay
6-Blank
N/A
7-BU ** K005 DLB Relay to Ring Element
X204 1-YE K206 to Broil Element
2-Not Used
N/A
3-Blank
N/A
4-BK
L1 to K206 Relay
5-BK
L1 to K206 Relay
X210 1-BU High Temperature Cutout (HTC)
2-Blank
N/A
3-BU
High Temperature Cutout (HTC)
LOWER CAVITY SMALL LOAD
X205 1-YE ** K212 Relay to Convection Fan
2-RD
L2 to K217 Relay
3-BN
K216 to Light Transformer
4-Not Used
N/A
5-Not Used
N/A
6-BN K217 Relay to Motorized Door Latch (MDL)
X206
1-YE
Door Switch
2-YE
Latch Switch
3-YE/BK
Latch Switch
4-OR/BK
Latch Switch
5-Not Used N/A
PLUG NO
PIN NO
FROM/TO
6-VT/WH
Door Switch
7-BN/WH
Door Switch
X207 1-WH Hall Effect Sensor
2-Not Used
N/A
3-WH Temperature Sensor
4-RD
Hall Effect Sensor
5-BK
Hall Effect Sensor
6-WH Temperature Sensor
X209
1-BU/WH
X105-P3 to Cooling Fan (L)
2-BU X105-P4 to Cooling Fan (H)
* Not used on M271, M301 ** MED only
To remove the PC control module:
1. Disconnect all wires.
2. Remove 1 T20 screw securing control module to chassis.
3. Slide module to the left to release the 3 tabs on the bottom of
the module bracket from the 3 slots in the chassis.
After replacing the relay board, always confirm that the option code is
set correctly, reset the oven, and test operation. See section 7.2
Service Mode/Setting Option Code for additional information.
6.11 Power Supply Module
The power supply module (9.6V 12.5W) provides DC voltage to the
control module and user interface.
Table 6 Plugs and pins on the PC control module