Thermador Masterpiece ME271E Series User manual

SERVICE MANUAL
for
Thermador
Masterpiece Series
Built-in Wall Ovens
This manual contains information that is necessary for
servicing the following Thermador electric built-in wall
ovens:
M271ES, ME271Ex, ME272ES, MED272Ex,
MEM271Ex, MEMW271Ex, M301Ex, ME301Ex,
ME302Ex, MED302Ex, MEW301ES, MEM301ES,
MEMW301ES, MEMCW301Ex
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.
Models:
M271ES, ME271Ex, ME272ES, MED272Ex,
MEM271Ex, MEMW271Ex, M301Ex, ME301Ex,
ME302Ex, MED302Ex, MEW301ES,
MEM301ES, MEMW301ES, MEMCW301Ex

Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
TABLE OF CONTENTS
1General........................................................................................3
1.1 Models...................................................................................3
1.2 Features and Options............................................................3
1.3 Data Plate..............................................................................4
1.4 Warranty................................................................................4
2Operation.....................................................................................4
2.1 Element Duty Cycles.............................................................4
2.1.1 Using Table 3 (Element Duty Cycles During Preheat)...5
2.2 Sequence of Events..............................................................6
2.3 Cooling Fans.........................................................................7
3Component Accessibility...........................................................8
3.1 Serviceable from Front..........................................................8
3.2 Serviceable from Top............................................................8
3.3 Serviceable from Rear...........................................................8
4Service and Repair.....................................................................8
4.1 Doors.....................................................................................8
4.1.1 Removing and Replacing the Door(s)............................8
4.2 Door Latch/Motor Assembly..................................................9
4.3 Lamps....................................................................................9
4.3.1 Replacing Lamps .........................................................10
4.4 High Temperature Cutout (HTC).........................................11
4.5 Convection Fan and Ring Element......................................11
4.6 Temperature Sensor ...........................................................11
4.6.1 Setting Temperature Offsets........................................11
4.7 Broil Element.......................................................................12
4.8 User Interface......................................................................12
4.8.1 Removing the User Interface .......................................12
4.9 PC Control Module (Relay Board).......................................13
4.10 Power Supply Module......................................................16
4.11 Halogen Light Transformer(s)..........................................16
4.12 Convection Fan Motor .....................................................17
4.13 Bake Element (Upper Oven)............................................17
4.13.1 Removing the Bake Element........................................17
4.13.2 Reinstalling the Bake Element.....................................17
4.14 Cooling Fan Motor (Upper Oven) ....................................17
5Error Codes .............................................................................. 18
5.1 Error Code Table ................................................................ 18
5.2 Service Mode / Setting Option Code .................................. 19
5.3 Entering Service Mode ....................................................... 19
5.4 Setting Option Code ........................................................... 19
5.5 Exiting Service Mode.......................................................... 19
5.6 Resetting the Oven............................................................. 19
5.7 Option Codes...................................................................... 19
6Demo Mode............................................................................... 20
7Troubleshooting....................................................................... 20
7.1 Fault Tree Diagram............................................................. 21
7.2 Fault Tree ........................................................................... 23
7.3 Testing................................................................................ 31
8Wiring Diagrams and Schematics.......................................... 31
8.1 Wire Color Key.................................................................... 31
8.2 Strip Diagrams.................................................................... 32
9Additional References............................................................. 32
9.1 QuickFinder ........................................................................ 32
9.2 Technical Support............................................................... 32
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
Page 3 of 33
1 GENERAL
There are 15 M/ME models in various combinations included in the
2007 Thermador Masterpiece Built-in Wall Oven (BIWO) Series.
These models utilize A, B, and C oven cavities, and combination
models include a built-in variation of the WD27/WD30 warming drawer
and/or a convection (MCEx) or traditional (MBEx) microwave.
All models have a glass user interface (touch panel) with graphical
displays. Fast preheat capability, 2-hour self-clean, telescopic racks,
and up to 16 cooking modes are among the features offered.
The control panel and door skins on the stainless models are grade
304 stainless steel.
Models ending in EP (introduced in 2008) have Pro handles; all others
have Masterpiece handles.
1.1 Models
27” Ovens
M271ES Single oven with convection
ME271Ex Single oven with true convection
ME272ES Double oven with true convection/thermal
MED272Ex Double oven with true convection both cavities
MEM271Ex Combination with microwave and true
convection oven
MEMW271Ex Combination with microwave, true convection
oven, and warming drawer
MEMCW271ES Combination with convection microwave, true
convection oven, and warming drawer (new in
2008)
30” Ovens
M301ES Single oven with convection
ME301Ex Single oven with true convection
ME302Ex Double oven with true convection/thermal
MED302Ex Double oven with true convection both cavities
MEW301Ex Combination with true convection oven and
warming drawer
MEM301ES Combination with microwave and true
convection oven
MEMC301Ex Combination with convection microwave and
true convection oven
MEMW301ES Combination with microwave, true convection
oven, and warming drawer
MEMCW301Ex Convection microwave with true convection
oven and warming drawer
1.2 Features and Options
Tables 1 and 2 reflect the cavity configuration and the features
available in each model.
Table 1 Thermador 27” Masterpiece Features by Model

Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
Data
p
late
1.3 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 87 were built in
2007; 88 = 2008; 89 = 2009, etc.
Table 2 Thermador 30” Masterpiece Features by Model
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.
1.4 Warranty
The product is warranted to be free from defects in materials and
workmanship for a period of 12 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
Manual.
2 OPERATION
2.1 Element Duty Cycles
A new 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,
Figure 1 Data plate
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
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. The table below 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.
2.1.1 Using Table 3 (Element Duty Cycles During Preheat)
In Table 3, 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 (see Cavity C):
ME302ES built in 01/2008 (see columns labeled 1)
•Bake Element: After initial 30 seconds of the cycle, element
turns on and remains on for the final 30 seconds of the cycle.
•Ring Element: After initial 30 seconds of the cycle, element
turns on and remains on for the final 30 seconds of the cycle
(same as Bake Element).
•Broil Element: Turns on at the beginning of the cycle (0) and
remains on for the first 30 seconds of the cycle.
ME302ES built in 08/2008 (see columns labeled 2)
•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.
Table 3 Element duty cycles during preheat by cavity type.
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
2.2 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 Figure 3 Sequence of Events during Preheat: Convection Broil/Broil modes
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
Page 7 of 33
Fi
gure 5 Sequence of Events during Preheat: Self-clean mode
Figure 4 Sequence of Events during Preheat: True Convection
2.3 Cooling Fans
Cooling fans 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°.
(Early models were programmed with a lower shut-off temperature,
which resulted in a longer running time for the cooling fan.)

Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
3 COMPONENT ACCESSIBILITY
3.1 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.
3.2 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:
Halogen light transformers
Terminal block
Power supply
3.3 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)
4 SERVICE AND REPAIR
m CAUTION
9Sheet metal parts often have sharp edges. Avoid injury by
handling these parts with care.
9Turn off the electrical power circuit to the oven at the main junction
box before servicing this unit.
9For those checks requiring the use of electrical power, exercise
extreme care.
4.1 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.
Models ending with Customer Service Index (KI) /01 (and /02 warming
drawer combo models) were produced with 4-pane doors.
Subsequent models have 3-pane doors.
4.1.1 Removing and Replacing the Door(s)
m CAUTION
Avoid injury when removing and replacing oven doors.
9Be sure oven is cool enough for handling.
9Position hinges properly (see Figure 6).
9Grasp only by sides, not by the handle.
9Do not force door open or closed.
9Handle with care–door weighs ~38 pounds.
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
To remove the door:
1. Open door completely.
2. Flip hinge levers back to open as shown below.
3. Close door until it remains open ~6 inches.
4. Using both hands, lift door up and out.
To replace the door:
1. Position door as if it were open ~6 inches and insert hinges
into slots.
2. Open door completely.
3. Flip hinge levers forward to close as shown below.
4. Close and open door to check operation.
•Hinges should be replaced in pairs.
•Masterpiece ovens do not have serviceable hinge receivers.
4.2 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.
If the latch becomes stuck in the locked position, turning the unit off
and back on will open the latch if the cavity temperature <450°. If latch
is stuck in partially locked position, press SELF CLEAN, then ON/OFF.
The latch can be tested in Service Mode.
To remove the latch/motor assembly:
Figure 6 Opening the hinge lever
1. Remove 3 T20 screws securing trim piece to frame (do not
remove 2 screws on either side of latch).
2. Pull trim forward about 1”, then slightly to the right or left to
clear the screw tab (see Figure 8).
3. Slip hands under trim and lift upper plate while sliding trim and
latch toward you.
Lock/
Unlock
Switch
Door
Switch
Screw
Tab
Figure 7 Closing hinge lever
Figure 8 Door latch/motor assembly
4.3 Lamps
All 27” Masterpiece ovens have two halogen lamps per cavity (one on
the side and one on the cavity ceiling), and 30” ovens have three
lamps per cavity (one on each side, and two on the cavity ceiling).
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
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.
4.3.1 Replacing Lamps
Use 10-watt, 12-volt bi-pin halogen light bulbs (Part # 150188).
Halogen bulbs must be handled with a clean, dry cloth.
4.3.1.1 Side Lamp (Vertical-style)
1. Remove racks and rack support.
2. Firmly push the top mounting clip up and back (toward oven
wall), until it releases the glass cover.
3. Pull the halogen bulb straight out from its socket.
4. Using a clean, dry cloth, insert the new bulb.
5. Reinsert the bottom of the glass cover (smooth side out) into
the bottom clip, and firmly push the top of the cover into the
upper clip until it snaps into place.
4.3.1.2 Side Lamp (Horizontal-style)
1. Remove racks and rack support.
2. Slide tip of flat-blade screwdriver between fixing clip and lamp
housing, while supporting lens cover along bottom edge.
mCAUTION
9Turn off power to the oven at the fuse or breaker box–light socket
is live with door open.
9Be sure oven and lights are cool to the touch.
9Handle glass lenses carefully.
Slide screwdriver
between fixing clip
and lamp housing.
Figure 10 Horizontal-style side lamp
Holder
clip
3. Gently twist screwdriver to loosen the lens cover.
4. Remove cover and fixing clip.
5. Grasp halogen bulb and pull it straight out from its socket.
6. Using a clean, dry cloth, insert new bulb into socket.
7. Reinsert lens cover into the holder clip and gently push back
until fixing clip snaps into place.
Top
mounting
clip 4.3.1.3 Ceiling Lamp
1. Unscrew glass cover.
2. Pull bulb straight out of its socket.
3. Using a clean, dry cloth, insert the new bulb.
4. Replace the glass cover.
Figure 9 Vertical-style side lamp
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
Ta
4.4 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.
ble 4 Normal temperature sensor resistance readings
4.5 Convection Fan and Ring Element
All models in the Masterpiece Series are configured with convection
capabilities in one or more oven cavities. The M models have a
convection fan only (cavity type B), and the ME models have both a
convection fan and a convection (also called a “ring” or “3rd”) element,
which gives the ovens true European convection capability (cavity
type C). The lower cavity of the ME272ES and ME302Ex offer strictly
thermal heating (cavity type A).
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.
4.6 Temperature Sensor
Use an ohmmeter to check the resistance of the sensor. Normal
ranges (based on cavity temperature) are shown in Table 4.
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.
4.6.1 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…
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
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.
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.
4.7 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.
4.8 User Interface
Figure 11 reflects the 3 variations of the T1 User Interface used in the
Masterpiece Series ovens.
nM271, M301 oAll single/combo ME models
pME272, ME302, MED272, MED302
nT1S1
oT1S2
pT1D
The user interface control board is assembled onto a chassis and the
entire assembly is serviced as a single unit.
Figure 11 T1 User Interface variations
4.8.1 Removing the User Interface
1. Slide unit out from wall ~ 4 inches.
2. Remove 2 T20 bolts from each side.
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
3. Grasp one corner of the interface panel and lift upward, then
pull it toward you (see Figure 12).
4. Repeat on the other side.
5. Disconnect the 3-wire yellow harness leading to PC control
module.
To remove the user interface board and chassis from the manifold
bracket, remove the 10 binding-head T20 screws securing the
interface chassis to the bracket (these screws are unique to the
interface – notice the serrated underside).
If the user interface assembly was difficult to remove, break the metal
tabs off (n) to make it easier to reinstall; use pliers to bend the tabs
back and forth until they break off.
After installing a new user interface board, always reset the oven and
test.
4.9 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 13.
Whenever possible, conduct troubleshooting tests at the control
module. Refer to Figures 14 -15 for plug and relay locations.
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.
1
2
Figure 13 PC Control Module is visible after removing access panel.
Figure 12 Each side of the user interface bracket has a tab nthat rests
in a slot on the chassis u-
p
rofile o.
Figure 14 Plug locations on the double oven control module
X101 X102 X107
X103 X104 X105 X106
X1
X2
X3
X209
X210 X110
X204
Rear
Front
X202 X201 X207
X206
X203 X205
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
Figures 15 Relay locations on the double oven control module
Use Table 5 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
connector - YE Control Module to Factory Service Port
X108* 2-position card-edge
connector - WH/GN Control Module to Meat Probe
UPPER/SINGLE CAVITY ELEMENTS
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
X101
6-BU K104 Relay to Ring Element
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
X102
5-RD L2 to K003 DLB Relay
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
X103
7-Blank N/A
1-Blank N/A
2-Blank N/A
X104
3-Blank N/A
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
PLUG NO PIN NO FROM/TO
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
1-BU High Temperature Cutout (HTC)
2-Not Used N/A
X110
3-BU High Temperature Cutout (HTC)
UPPER/SINGLE CAVITY SMALL LOAD
1-Blank N/A
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)
X105
8-RD L2 to K117 Relay
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
X106
7-BN/WH Door Switch
1-WH Hall Effect Sensor
2-BK Hall Effect Sensor
3-RD Hall Effect Sensor
4-WH Temperature Sensor
X107
5-WH Temperature Sensor
1-BU High Temperature Cutout (HTC)X110 2-Not Used N/A
PLUG NO PIN NO FROM/TO
3-BU High Temperature Cutout (HTC)
LOWER CAVITY ELEMENTS
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
X201
7-OR K202 Relay to Bake Element
1-RD L2
2-RD L2 to K006 DLB Relay
3-Not Used N/A
4-Not Used N/A
X202
5-YE K006 DLB Relay to Broil Element
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
X203
7-BU ** K005 DLB Relay to Ring Element
1-YE K206 to Broil Element
2-Not Used N/A
3-Blank N/A
4-BK L1 to K206 Relay
X204
5-BK L1 to K206 Relay
1-BU High Temperature Cutout (HTC)
2-Blank N/A
X210
3-BU High Temperature Cutout (HTC)
LOWER CAVITY SMALL LOAD
X205 1-YE ** K212 Relay to Convection Fan
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
Always reset the oven and test after changing the control module. In
some cases, a second reset may be necessary.
PLUG NO PIN NO FROM/TO
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)
1-YE Door Switch
2-YE Latch Switch
3-YE/BK Latch Switch
4-OR/BK Latch Switch
5-Not Used N/A
6-VT/WH Door Switch
X206
7-BN/WH Door Switch
1-WH Hall Effect Sensor
2-Not Used N/A
4.10 Power Supply Module
The power supply module (9.6V 12.5W) provides DC voltage to the
control module and user interface.
4.11 Halogen Light Transformer(s)
One transformer (120V-12V 40VA) is utilized per cavity. Triac
switches 120 VAC to the transformer. There are 4 terminals on the
new transformer, as shown in Figure 16.
The resistance between the primary terminals should measure ~12.8
ohms and the resistance between the secondary terminals should
measure ~0.32 ohms.
3-WH Temperature Sensor
4-RD Hall Effect Sensor
5-BK Hall Effect Sensor
X207
6-WH Temperature Sensor
1-BU/WH X105-P3 to Cooling Fan (L)X209 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.
Secondary
LINE
Terminals
Primary
LOAD
Terminal
OR
OR
X105-6
X205-4
Terminal
Block
BN
WH
LINE LOAD
Table 5 Plugs and pins on the PC control module
Page 16 of 33
Figure 16 Halogen light transformer

Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
6. Tuck insulation up into the oven wall as necessary.
4.12 Convection Fan Motor 7. While holding element terminals, lift element upward to clear
the outer edge of the compartment.
The convection fan motor is 120V 29W. To test the motor, check for
120V across X105 / Pin 2 (upper/single) or X205 / Pin 1 (PODC) and
chassis ground or neutral. 8. Hold element on both sides and lift upward as you slide it
straight out.
The motor is accessible from the rear, after removing the rear outer
sheet metal panel. 4.13.2 Reinstalling the Bake Element
There are 2 tabs inside the element cavity, and the front tab will
prevent the element from going in all the way. Use a ruler or the
vertical air channel (after removing plastic purse locks) as a tool to
guide the element back in.
1. Disconnect the 2 wires from the motor terminals.
2. Remove 3 T20 screws from the arms of the motor assembly.
3. Use a tap and a hammer to dislodge the assembly from the
clips that secure it to the rear of the unit. (Position tap on the
arm secured by the rightmost clip.) 1. Place the tool inside the cavity, on top of the tab, then insert
the element on top of the tool and slide it in.
2. After the element is beyond the front tab, remove the tool.
4.13 Bake Element (Upper Oven) 3. Complete the installation.
Refer to the Strip Element Diagram to test the element (240V 2000W)
at the control module, or disconnect the wires from the terminals and
use a meter to check for a reading of ~29 ohms.
4. Replace the plastic purse locks clips if they were removed
from the vertical air channel.
4.14 Cooling Fan Motor (Upper Oven)
To clear a path for removing the bake element, it is necessary to
remove the vertical air channel(s) and disconnect wires. Before
proceeding, note the position of the wires. Each 2-speed cooling fan (120V 28/41W) has 3 terminals (high
speed, low speed, and neutral) and a Hall effect sensor. There is tape
around the motor windings and the terminals are labeled N, H, and L
for reference, as shown in Figure 17.
4.13.1 Removing the Bake Element
1. Pull wires out of plastic purse locks attached to upper and
lower vertical air channels.
2. Remove upper air channel (4 T20 screws).
3. To create a pathway for the bake element, disconnect OR
wires from upper and lower bake element terminals; YE from
convection element terminals, BU/WH, BU, and WH from
cooling fan motor.
4. Drape the wires/harnesses to the side so they do not block the
element as it is pulled out.
Figure 17 Tape on cooling fan windings marked to designate terminals
5. Remove the screw between the element terminals.
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
If the Hall effect sensor does not detect fan rotation, an error will
display. To test the upper fan at the control module, check voltage
across X105 / Pin 3 or 4 and neutral.
1. Remove 3 T20 screws securing the fan to the mounting
bracket.
2. Remove 3 T20 screws securing the bracket to the oven
housing.
3. Slide bracket up and out to release it from the 2 tabs holding it
in position.
4. Remove 3 T20 screws from the right side of the unit’s top
panel.
5. Lift the right corner of the top panel and remove the fan/motor.
5 ERROR CODES
A Service Guide with error code information, wiring diagrams, and
instructions for entering Service Mode (if applicable) is packed with
every unit. Find it on the underside of the upper plenum access panel
as shown in Figure 18.
5.1 Error Code Table
The following table is included in the oven Service Guide. The error
codes which begin with E2 apply to the lower cavity of double ovens.
Diagrams referenced in the table can also be found in the appropriate
Service Guide.
CODE DESCRIPTION CAUSE/ACTION
E000 Wrong module combination Control module and user
interface are mismatched. Set
Option Code properly.
E003 Electronics too hot User interface exceeds
185°F/85°C
E005 Communication error Loss of communication
between user interface and
control module at start-up.
Check for ~4.9Vdc on middle
pin of communication
harness. Check connections
of all communication lines
and control module inputs.
E009 ROM check error in user interface User interface not getting all
information from control
module at start-up. Check for
loss of communication or
disconnected wire
somewhere in unit
E010 Data memory error in user interface
E011 Continuous pushing of single key Check user interface
assembly. Inspect touch
PCB.
Figure 18 Location of Thermador Built-in Oven Service Guide
E012 Defective User Interface PCB temp.
sensor
E014 ON/OFF key does not work
E032 Continuous pushing of keys 10 seconds of multiple keys
being pressed.
E101/E201 Cvt 1/Cvt 2 Temp. sensor open Refer to Diagram 2/4
E104/E204 Cvt 1/Cvt 2/Temp. sensor shorted Refer to Diagram 2/4
E106/E206 Cvt 1/Cvt 2 Door latch does not lock Refer to Diagram 2/4
E107/E207 Cvt 1/Cvt 2 Door latch does not
unlock Refer to Diagram 2/4
E115/E215 Cvt 1/Cvt 2 Temp. in unlocked cavity
too high
E116 Cvt 1/Cvt 2 Probe error Standard probe module is
part of the control module.
Refer to Diagram 1.
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
5.4 Setting Option Code
CODE DESCRIPTION CAUSE/ACTION
E118/E218 Cvt 1/Cvt 2 Cooling fan supervision
error Cooling fan speed is too low or too high. Refer to Diagram
2/4. Ensure wire harness not
touching motor or pinched.
Confirm plenum not touching
fan end cap. Check Hall
Effect Sensor connection.
5. Locate the 4-digit code on the label near the PC control
module in the upper plenum of the oven, or in the table below.
6. Press
FAST PREHEAT to advance to the Option Code menu
selection.
7. Press
START, and enter appropriate 4-digit option code .
E122 Cvt 1/ Probe sensor temp. too high
or shorted. Check probe receptacle and harness. 8. To confirm the change after the code has been entered, press
FAST PREHEAT to advance to the next menu item.
E123 Cvt 1/ Probe sensor temp. too low
E124/E224 Cvt 1/Cvt 2 Door switch error Door switch is in undefined
state. Refer to Diagram 2/4. 5.5 Exiting Service Mode
E126/E226 Cvt 1/Cvt 2 Door latch error Door latch is in an undefined
state. Refer to Diagram 2/4. 9. Press ON/OFF to exit Service Mode.
10. Follow the instructions on the display to set the time and date.
E303 Electronics too hot Control module exceeds
212°F/100°C.
E309 ROM Check error in control module 5.6 Resetting the Oven
E310 Data memory error in control module
E312 Defective control module PCB temp.
sensor 11. Unplug the unit or turn the power off at the circuit breaker for
30 seconds.
12. Follow the instructions on the display to set the time and date.
Table 6 Error codes 13. Confirm that the error code has been cleared and the oven is
functioning normally.
5.2 Service Mode / Setting Option Code 5.7 Option Codes
When both the user interface board and control module (relay board)
are replaced, the oven will display E000 (Wrong Module Combination)
fault code at start-up. To resolve, place the unit in Service Mode and
manually set the Option Code.
Model
5.3 Entering Service Mode
1. Press and hold START.
2. Press and hold FAST PREHEAT.
3. Press
ON/OFF.
4. Release all three buttons.
Option Code Model Option Code
M271ES 0240 MEM271EB / ES 0341
M301ES 0250 MEM301ES 0351
ME271EB / ES 0341 MEMC301EB / ES 0351
ME272ES 0841 MEMCW301EB / ES / EP 0351
ME301EB / ES / EP 0351 MEMW271EB / ES 0341
ME302ES / EP 0851 MEMW301ES 0351
MED272EB / ES 0941 MEW301ES 0351
MED302EB / ES 0951
Table 7 Masterpiece Oven Option Codes
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Service Manual for Thermador Masterpiece Series Built-in Wall Ovens
6 DEMO MODE
The display and lights will work on 120VAC when the black and red
wires are tied together.
7 TROUBLESHOOTING
Use the Fault Tree Diagram and Fault Tree on the following pages to
guide troubleshooting efforts.
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