Thermador Appliance Error Codes
Range & Stove
Pro Grand and Masterpiece range error codes for oven sensors, door locks, heating elements, and control board faults. Thermador uses both F-series (older models) and E-series codes (newer platforms).
F2 / E
Oven Temperature Too Hot
Oven exceeded safe temperature — relay board or RTD sensor fault
What This Means
F2 on Thermador ranges indicates the oven temperature has exceeded its safe upper limit. The oven shuts off as a safety measure. This can occur during normal cooking or self-clean cycles. On newer Thermador ranges, this may appear as a generic "E" code with a number. Confirmed by PartSelect Thermador fault code documentation.
Common Causes
- Relay board stuck in closed position — element never turns off
- Faulty RTD temperature sensor reading too low, causing the board to overheat the oven
- Control board (clock) sending incorrect signals to the relay
What You Can Try
Press TIMERS or any key to stop the beeping. Turn off the oven and reset at the circuit breaker for 30 seconds. Measure the RTD sensor resistance — should read approximately 1,080 ohms at 70°F. If resistance is off, replace the sensor. If sensor is correct, the relay board requires professional replacement.
F3 / E3
Open Oven Temperature Sensor (RTD)
Temperature probe circuit is open — no signal reaching the control board
What This Means
F3 (older models) or E3 (newer models) means the oven temperature sensor's circuit is open — completely broken. The control board receives no temperature feedback and cannot safely operate the oven heating system. Confirmed by PartSelect Thermador fault code documentation and Sears PartsDirect Masterpiece oven service guide.
Common Causes
- RTD sensor probe physically broken or burned
- Sensor wiring harness damaged or connector pulled loose
- Wire burned through during a high-temperature self-clean cycle
What You Can Try
Disconnect power and inspect the sensor probe on the oven back wall for visible damage. Check the wiring harness connections between the sensor and control board. Reconnect any loose connectors. If wiring is intact, test sensor resistance with a multimeter — 1,080 ohms at 70°F is the Thermador specification. Replace the RTD sensor if it reads open (infinite resistance).
F4 / E4
Shorted Oven Temperature Sensor (RTD)
Temperature probe short-circuited — reading impossibly low values
What This Means
F4/E4 is the counterpart to F3/E3 — instead of an open circuit, the RTD sensor is short-circuited, reading near-zero resistance. The control board interprets this as an impossibly cold oven and may overheat the cavity trying to reach setpoint. Both F3 and F4 are confirmed Thermador Masterpiece fault codes per PartSelect and Sears PartsDirect service documentation.
Common Causes
- Water or food spill contacting the sensor probe or connector
- Insulation on sensor wiring worn through causing wires to contact each other
- Sensor probe physically damaged — cracked ceramic body
What You Can Try
Disconnect power. Check the sensor harness for any visible wire-to-wire contact or chafing. Test the RTD with a multimeter — a shorted sensor reads close to 0 ohms (should be ~1,080 ohms at room temp). Replace the RTD temperature sensor. If F4 returns after sensor replacement, the control board relay is suspect.
F9 /
E9 / E11
E9 / E11
Door Latch Fault
Self-clean door lock not engaging or confirming — latch motor or switch failure
What This Means
F9, E9, and E11 all indicate door latch faults on Thermador ranges and wall ovens. The door lock is required before pyrolytic self-clean can begin — if the latch doesn't engage or the switch doesn't confirm the locked state, the program is aborted. Confirmed by PartSelect Thermador fault code table and Sears PartsDirect Masterpiece oven guide.
Common Causes
- Oven racks left inside blocking the latch mechanism
- Latch hook worn, bent, or misaligned
- Door latch motor failed or stalled
- Door latch switch not confirming locked position
What You Can Try
Remove all oven racks. Press TIMERS to clear the beep. Check the door latch mechanism at the top of the oven door for visible obstruction or misalignment. Reset power at the breaker for 30 seconds. Attempt self-clean again. If the latch motor hums but the door won't lock, the latch assembly requires professional replacement.
E+NUM
General Electronic Fault
E code with beeping — control board detected an internal fault
What This Means
Thermador's official support page confirms: when "E" and a number appear on the range display with beeping, it indicates an internal electronic fault detected by the control system. The specific number further identifies the subsystem affected. Thermador instructs customers to press TIMERS to stop beeping, reset if necessary, and call 1-800-735-4328 if the code persists.
Common Causes
- One-off power fluctuation triggering a false fault (often self-resolving)
- Control board fault requiring diagnosis by Thermador-certified technician
- Home Connect software update error (E0211, E1601, E0510 — specific to WiFi-enabled models)
What You Can Try
Press TIMERS or any key to stop the beeping. Turn off the oven. Reset at the circuit breaker for 30 seconds. Touch any control within 3 minutes of restoring power to reactivate. If the code was a one-off, it will clear. If it reappears on the same display, call Thermador Customer Support at 1-800-735-4328 and provide the exact code.
F5
Cooktop Voltage Fault (Range Induction)
F5 flashing with power level — incorrect voltage at induction cooking zone
What This Means
On Thermador ranges with induction cooktops, F5 flashing alternately with a power level indicator signals a voltage supply fault at the cooking zone. Confirmed by Thermador's official ranges error code page. The cooking zone shuts down to prevent damage to the power electronics.
Common Causes
- Incoming voltage too high or too low from the utility supply
- Incorrect electrical connection at installation
- Brownout or utility voltage fluctuation event
What You Can Try
Do not continue using the affected cooking zone. Contact your electrical utility provider or Thermador Customer Support at 1-800-735-4328. A licensed electrician should verify that the incoming supply voltage matches the range's specifications before the zone is reactivated.
Coffee Machine
Built-in Thermador coffee machine fault messages and display alerts. Verified against Thermador USA official support and troubleshooting pages.
BAD
VOLT
VOLT
Supply Voltage Out of Range
Power supply too high or too low — appliance locked out
What This Means
Thermador's official coffee machine troubleshooting page confirms this message appears when the voltage supplied to the machine is too high or too low. The machine locks out all functions to prevent damage. This is not a machine fault — it is a power supply issue.
Common Causes
- Utility brownout or overvoltage event
- Shared circuit with high-draw appliances causing voltage sag
- Incorrect installation wiring
What You Can Try
Contact your electricity or grid provider and have your power supply checked by a licensed electrician. Do not attempt to operate the machine until the voltage issue is resolved — sustained voltage irregularities can cause irreversible damage to the heating electronics.
COOL
DOWN
DOWN
OVER
HEAT
HEAT
Machine internal temperature too high — 30-minute cool-down required
What This Means
Thermador's official troubleshooting page confirms this message: the coffee machine's internal temperature is too high. All brewing functions are suspended. This is most commonly caused by running multiple consecutive brewing cycles without allowing adequate cool-down time.
Common Causes
- Multiple consecutive brew cycles without rest time between them
- Machine installed in an enclosed cabinet with inadequate ventilation
- Descaling overdue — scale buildup causing the heater to work harder and overheat
What You Can Try
Switch off the coffee machine for 30 minutes and allow it to cool completely. Ensure the installation provides adequate ventilation clearance per the installation guide. After cool-down, run a descaling program if it has not been done recently. Persistent overheating alerts after descaling indicate a heater or thermostat issue requiring professional diagnosis.
NO
BEANS
BEANS
Bean Hopper Empty or Beans Not Falling
No beans detected in the grinder — container empty or beans too oily
What This Means
Thermador confirms two causes for this message: the bean container is actually empty, or the beans are too oily and are clumping rather than falling into the grinding unit. Dark-roasted and flavored beans have high oil content that causes bridging in the hopper.
Common Causes
- Bean container empty — refill required
- Oily or dark-roast beans bridging across the hopper opening
- Bean container not seated correctly
What You Can Try
Refill the bean container if empty. If the container is full, gently tap or shake the container to dislodge the beans — Thermador's official instructions confirm this resolves the oily-bean issue. Clean the bean container with a dry cloth if oily residue has built up on the walls. Switch to less oily beans if the problem recurs frequently.
ERR 8
Hopper / Brew Mechanism Jammed
Coffee grounds hopper system jammed — mechanical fault in grounds path
What This Means
Error 8 on Thermador built-in coffee machines (BICM24CS and similar models) indicates the hopper mechanism has jammed and is not completing its cycle. Field reports and Fixya technical documentation confirm this is often caused by a broken spring in the hopper swing cover — the small black swing unit that guides grounds into the brew unit. When the spring breaks, the hopper guide disengages from its slot and jams, preventing the machine from detecting cycle completion.
Common Causes
- Broken spring in the hopper swing cover unit — known failure point on BICM series
- Dried coffee grounds accumulation jamming the mechanism
- Hopper guide dislodged from its guide slot
What You Can Try
Empty the bean hopper and visually inspect the hopper swing cover mechanism for the small black swing unit. Check if the spring is intact and the guide is seated in its slot. Clean all grounds from the mechanism. If the spring is broken (this is a known defect on the BICM series), the hopper assembly requires professional parts replacement. Contact Thermador Service at 1-800-735-4328.
DE-
SCALE
SCALE
Descaling Required
Limescale buildup detected — descaling program must be run
What This Means
Thermador's official support page confirms: the coffee machine needs to be descaled. The machine has tracked usage and determined that limescale buildup in the thermoblock has reached a level that will affect performance and, if left unaddressed, lead to overheating faults and heater failure.
Common Causes
- Regular use in hard water areas without a water filter
- Descaling interval exceeded — Thermador recommends every 2–3 months in hard water
- Water filter not replaced on schedule, allowing scale through
What You Can Try
Run the descaling program immediately using genuine Thermador descaler (available in the Thermador Accessories Store). Follow the on-screen instructions. Do not use vinegar — it can damage internal seals. Also replace the water filter per your model's schedule. Ignoring the DESCALE alert leads to LEAVE DEVICE TO COOL errors and eventual heater failure.
Dishwasher
Star Sapphire and DWHD series dishwasher error codes. Verified against Thermador USA official dishwasher error code support page and A to Z Appliance troubleshooting documentation.
E24 /
E25
E25
Drainage Fault
Dishwasher not draining — pump blocked, filter clogged, or drain hose kinked
What This Means
E24 and E25 are the most common Thermador dishwasher error codes. Confirmed by Thermador's official Canadian support page: E25 specifically indicates the drain pump is blocked, there is a drain issue, the filter is clogged, or the pump impeller is jammed. E24 typically points to a drain hose or airgap issue. Both are drainage system faults.
Common Causes
- Drain pump filter blocked with food debris — requires monthly cleaning
- Drain pump impeller jammed by a hard object (bone, glass chip)
- Drain hose kinked or sharply bent
- Airgap or sink drain clogged, preventing dishwasher from draining
- Drain pump cover loose — not clicked fully into place
What You Can Try
Remove and clean the dishwasher filter under running water (Thermador recommends monthly cleaning). Remove the drain pump cover, clear standing water and debris, and ensure the cover clicks fully back into place. Check the drain hose for kinks. Disconnect the drain hose and place it in a bucket to check for blockages. Turn off the appliance, check the airgap, then reconnect and run a rinse cycle. If E24/E25 persists, call Thermador at 1-800-735-4328.
E23 /
E6101
E6101
Drain Pump Fault
Drain pump failed or circuit fault detected
What This Means
E23 or E6101 indicates an issue with the drain pump motor itself — not just a blockage. Confirmed by A to Z Appliance Service Thermador documentation. Unlike E24/E25 (blockage), E23 points to a pump circuit or motor failure that will not resolve with cleaning.
Common Causes
- Drain pump motor failed — burned windings or seized bearings
- Pump circuit fault on the main control board
- Pump wiring harness damaged
What You Can Try
First clean and inspect the drain pump filter as for E24/E25 — in some cases a severe blockage can trigger E23. Reset at the circuit breaker for 30 seconds. If E23 returns on a clean filter, the pump motor or board requires professional diagnosis. Contact Thermador at 1-800-735-4328.
E04 /
E0105
E0105
Heater Electronics Fault
Fault detected in heater electronics during self-test
What This Means
E04 or E0105 is confirmed by A to Z Appliance documentation as a heater electronics fault detected during the dishwasher's self-test sequence. The appliance runs a self-test at start and has detected that the heater circuit is not functioning correctly.
Common Causes
- Heating element failed — open circuit
- Heater relay on the main control board failed
- Wiring harness to the heating element damaged
What You Can Try
Reset power at the circuit breaker for 30 seconds. Restart the dishwasher and allow the self-test to run. If E04/E0105 returns, the heating circuit requires professional diagnosis — the heating element and control board relay both need to be tested.
E27 /
E9001
E9001
Supply Voltage Too Low
Not an appliance fault — home electrical voltage is insufficient
What This Means
Thermador's official dishwasher support page explicitly states: E27 is not an appliance fault — the supply voltage is too low. E9001 also indicates power supply voltage is below the required minimum. The dishwasher protects itself from undervoltage damage by locking out operation.
Common Causes
- Utility brownout or sustained low voltage condition
- Shared circuit with heavy-draw appliances causing voltage drop
- Incorrect wiring at installation — undersized wire run
What You Can Try
Per Thermador's official instructions: have your home's voltage and electrical system checked by a professional electrician. Do not attempt to bypass or reset this code — undervoltage operation will damage the control board and motor over time.
E0100 / E0103 / E0110
Main Control Board Faults
Heat pump motor circuit, relay, or communication fault on the main board
What This Means
A to Z Appliance documentation confirms: E0100 = heat pump motor circuit fault on the main board; E0103 = main control board relay fault; E0110 = electronics miscommunication causing failure. These are all main control board-level faults on heat-pump dishwasher models. All three require professional service.
Common Causes
- Control board component failure — relay or motor driver circuit
- Power surge damaging the board
- Communication wiring fault between board modules
What You Can Try
Reset power at the circuit breaker for 30 seconds. If the code returns, contact Thermador Customer Support at 1-800-735-4328. Board diagnosis and replacement requires a certified Thermador technician with access to the specific board revision for your model.
Cooktop & Rangetop
Induction and electric cooktop error codes. Verified against Thermador official induction and electric cooktop error code pages. Gas rangetops do not display error codes.
OVER
HEAT
HEAT
Electronics Overheating — Zone Shutdown
Cooking zone electronics overheated — cool-down required before resuming
What This Means
Thermador's official induction and electric cooktop error code pages confirm: when an overheating error appears, the cooking zone has shut down because the electronics have reached an unsafe temperature. On induction models, a single zone may shut while others remain usable. The message will disappear once the electronics cool sufficiently.
Common Causes
- Sustained high-power cooking for extended periods
- Cabinet below the cooktop blocking the cooling fan airflow
- Very hot kitchen environment or ambient temperature
- Cooling fan inside the cooktop beginning to fail
What You Can Try
Wait until the electronics have cooled sufficiently — the error message will disappear automatically. Switch the affected cooking zone back on and continue cooking. Per Thermador's instructions, you can use remaining zones while the affected one cools. Ensure nothing in the cabinet below is blocking the fan. If the zone shuts down repeatedly under normal use, the cooling fan requires professional inspection.
BOARD
FAULT
FAULT
General Internal Electronics Fault
Cooktop detected an internal fault — power cycle required
What This Means
Thermador's official range and cooktop error code pages confirm: if an internal fault occurs, disconnect the appliance from the power supply for 30 seconds, then touch any control within 3 minutes of restoring power. If the fault was a one-off occurrence, the message will disappear. If it reappears, call Thermador at 1-800-735-4328 with the exact code.
Common Causes
- Transient power fluctuation causing a spurious fault
- Internal electronics fault requiring board diagnosis
- Communication error between cooking zone and main control module
What You Can Try
Disconnect the appliance from the power supply for 30 seconds (switch off the circuit breaker). Restore power and touch any control on the appliance within 3 minutes. If the fault clears, normal cooking can resume. If the error reappears immediately, call Thermador Customer Support at 1-800-735-4328 and provide the exact error code shown.
BAD
VOLT
VOLT
Incorrect Supply Voltage
Cooktop receiving incorrect voltage — contact utility or electrician
What This Means
Thermador's official cooktop error code page confirms: a voltage supply fault means the cooktop is not receiving the correct voltage. The appliance locks the affected zone to prevent damage. This is confirmed as an electrical installation or utility issue, not a cooktop defect.
Common Causes
- Incorrect installation wiring — wrong voltage configuration
- Utility overvoltage or undervoltage event
- Neutral wire issue at the electrical panel
What You Can Try
Do not continue using the cooktop. Per Thermador's official instructions: contact your electrical utility provider or call Thermador Customer Support at 1-800-735-4328. A licensed electrician must verify the incoming supply voltage and installation wiring configuration before the cooktop is reactivated.
LOW
BATT
BATT
CR2032 Battery Replacement Required
Induction cooktop memory battery dead — settings and clock lost on power interruption
What This Means
Thermador's official induction cooktop error code page confirms: this alert means the 3V CR2032 backup battery needs replacement. This battery maintains settings and the cooking sensor memory during power interruptions. The cooktop continues to function normally — this is a maintenance alert only.
Common Causes
- CR2032 battery depleted after several years of normal use
What You Can Try
Replace the 3V CR2032 battery per the instructions in your owner's manual. Thermador confirms this is a user-serviceable item. Download your owner's manual from Thermador.com if you do not have a copy. The cooktop will continue to operate normally while the battery is depleted — replace at your earliest convenience.
Oven
Masterpiece and Professional wall oven error codes. Verified against PartSelect Thermador fault code database and Sears PartsDirect Thermador Masterpiece oven service guide (RTD spec: 1,080 ohms at 70°F).
E2 / E3
/ E4
/ E4
Oven Temperature Sensor (RTD) Fault
RTD sensor out of range (E2), open-circuit (E3), or short-circuit (E4)
What This Means
Confirmed by PartSelect Thermador fault code table: E2 = RTD fault with incorrect reading; E3 = RTD open circuit (broken sensor); E4 = RTD short circuit. The Thermador Masterpiece wall oven RTD specification is 1,080 ohms at 70°F, confirmed by Sears PartsDirect service documentation. Without a valid RTD reading, the oven cannot heat safely.
Common Causes
- RTD probe damaged, burned, or physically broken inside the oven
- Wiring harness between RTD and control board damaged or disconnected
- Control board failure sending incorrect power to the RTD circuit
What You Can Try
Disconnect power and visually inspect the RTD probe on the oven back wall for damage. Check all harness connections. Measure the RTD with a multimeter — 1,080 ohms at 70°F is the correct reading. Replace the RTD if it reads open (∞) or shorted (~0 ohms). If sensor measures correctly, the control board is faulty.
E6 / E7
Oven Over-Temperature
E6 = overtemp during cooking; E7 = overtemp during self-clean cycle
What This Means
Confirmed by LA Appliance Fix Thermador oven error code documentation (which references the Thermador flash-code system): E6 = over-temperature during normal cooking operation (3 blue flashes, 2 heating flashes = code 32); E7 = over-temperature during the self-clean cycle (2 blue flashes, 3 heating flashes = code 23). Both require the oven to stop heating immediately.
Common Causes
- Relay board stuck closed — bake or broil element staying on permanently
- RTD sensor reading low, causing control board to overheat oven trying to reach setpoint
- Control board defect sending continuous heat signal
What You Can Try
Press TIMERS to clear the alarm. Do not use the oven until the fault is investigated — an oven that cannot stop heating is a fire risk. Reset at the breaker. If E6 or E7 returns, the relay board and RTD sensor both need professional testing. Disconnect power and call Thermador at 1-800-735-4328.
E9 / E11
/ E12
/ E12
Door Latch Switch Problem
Self-clean door latch switch or motor not confirming locked state
What This Means
Confirmed by PartSelect Thermador fault code table: E9 = door latch switch problem; E11 = door latch switch problem; E12 = door latch switch problem. These are all variations of the latch mechanism not confirming a secure lock before or during the self-clean cycle. Sears PartsDirect confirms checking latch switches and wiring as the first diagnostic step.
Common Causes
- Oven racks left inside blocking the latch
- Door latch switch worn or damaged — not making electrical contact
- Latch wiring harness loose or damaged
- Latch motor stalled
What You Can Try
Remove all oven racks. Press TIMERS to clear the beeping. Attempt the self-clean program again after ensuring the door closes and seals fully. Check the latch switch wiring connections. If the latch motor hums but does not lock, or E9/E11/E12 returns consistently, the latch assembly requires professional inspection and likely replacement.
E0211 / E1601 / E0510
Home Connect Software Update Error
WiFi connectivity error during Home Connect firmware update
What This Means
Thermador's official oven error code page specifically calls out E0211, E1601, and E0510 as errors that appear during Home Connect software updates on WiFi-enabled ovens. These are connectivity or update-related faults, not hardware failures. The oven continues to operate normally.
Common Causes
- WiFi connection dropped during an automatic firmware update
- Home Connect app update interrupted
- Router configuration blocking the update connection
What You Can Try
Thermador's official page directs customers to click through to their Home Connect resolution page for step-by-step instructions specific to these codes. Ensure your WiFi network is stable, the Home Connect app is updated, and retry the firmware update process. The oven functions normally during this error — all cooking functions remain available.
Ventilation Hood
Thermador ventilation hoods do not display numeric error codes. Common functional faults and their causes are listed below.
NO
FLOW
FLOW
Poor or No Airflow
Fan runs but suction is weak — grease filters or blower clogged
What This Means
The hood fan motor runs and lights work, but airflow and grease-capture performance are significantly reduced. This is almost always a maintenance issue. Thermador hoods require regular grease filter cleaning and periodic charcoal filter replacement on recirculation models.
Common Causes
- Grease filters heavily saturated — restricting airflow (most common cause)
- Charcoal filter fully saturated on recirculation installations — cannot be cleaned, must be replaced
- External duct damper flap stuck closed
- Grease accumulation inside the blower wheel housing reducing fan efficiency
What You Can Try
Remove and clean the grease filters (most Thermador models allow dishwasher cleaning — confirm in your manual). For recirculating hoods, replace the charcoal filter — it cannot be cleaned. Inspect the external duct flap to confirm it opens freely when the fan runs. If suction remains poor after filter service, the blower housing has grease accumulation and requires professional cleaning.
NO
LIGHT
LIGHT
Hood Lighting Not Working
One or more cooktop lights have failed
What This Means
One or more LED or halogen cooktop lights on the hood have failed. On halogen models, bulbs can often be user-replaced. On newer LED-integrated Thermador hood models, the LED module must be replaced professionally.
Common Causes
- Halogen bulb burned out — end of bulb life (user-replaceable)
- LED module failed on newer models
- Control switch fault — light switch on the circuit board
What You Can Try
Consult your model's manual to determine if the bulb type is user-replaceable. On halogen models, power off and allow to cool before replacing with the specified bulb — always use a cloth when handling halogen bulbs, as skin oils reduce bulb life significantly. On LED-integrated models, contact Thermador Service for module replacement.
FAN
NOISE
NOISE
Excessive Fan Noise or Vibration
Rattling or grinding noise during hood operation
What This Means
Rattling or grinding from the ventilation hood fan during operation typically indicates either grease-loaded fan blades causing imbalance, a loose grease filter vibrating in its frame, or a worn fan motor bearing. In most cases, this is a maintenance or installation issue.
Common Causes
- Grease filter not fully seated after cleaning — rattling in the frame
- Grease buildup on blower wheel blades causing imbalance
- Fan motor bearing worn — more common on units over 8 years
- Loose ductwork connection vibrating against the structure
What You Can Try
Remove and firmly reseat the grease filters — confirm they are fully locked into their clips. If noise persists, remove filters entirely and run the fan briefly to isolate whether the noise is from the filter or the blower. Tighten any accessible ductwork connections. If the noise is consistent and originating from the motor housing, professional bearing replacement is required.
Refrigerator
Freedom and T-series refrigerator error codes. Verified against Thermador Appliance Repair Service documentation and official Thermador refrigerator troubleshooting support page. Diagnostic mode: hold "Alarm Off" + "Setup" simultaneously for 5 seconds after power cycle.
E01
Refrigerator Sensor Fault / Short Circuit
Main control board cannot communicate with one or more refrigerator sensors
What This Means
Confirmed by Thermador Appliance Repair Service documentation: E01 indicates the main control board cannot communicate with one or more refrigerator sensors. This prevents the board from accurately monitoring and controlling refrigerator compartment temperature, which can result in temperature instability and food spoilage risk.
Common Causes
- Temperature sensor NTC open or short-circuit
- Wiring connector loose or corroded at the sensor or control board
- Control board failure preventing sensor communication
What You Can Try
Activate the diagnostic program: unplug the refrigerator for 5 minutes, restore power, then press "Alarm Off" and "Setup" simultaneously — "Load 0" should appear to begin diagnostics. A multimeter is required to test sensor continuity. Professional diagnosis is recommended given the diagnostic complexity.
E02
Freezer Sensor Fault
Main control board cannot communicate with one or more freezer sensors
What This Means
Confirmed by Thermador Appliance Repair Service: E02 is the freezer compartment counterpart to E01. The control board has lost communication with one or more freezer sensors. Without accurate freezer temperature monitoring, the compressor cannot maintain safe frozen temperatures and food spoilage risk is high.
Common Causes
- Freezer temperature sensor NTC failed — open or short circuit
- Freezer evaporator iced over, physically displacing the sensor from its mount
- Wiring harness to the freezer sensor compartment damaged
What You Can Try
If the freezer appears to have stopped cooling and has excessive frost, perform a manual defrost (unplug for 24–48 hours with doors open). If E02 returns within days after defrost, the sensor itself has failed and requires professional replacement. Move frozen food to backup storage immediately.
E05 /
E06
E06
Evaporator Sensor Fault
Refrigerator evaporator sensor unreachable or out of range
What This Means
Confirmed by Thermador Appliance Repair Service: E05 and E06 indicate the refrigerator evaporator sensor is unreachable. If the refrigerator is still cooling normally, this points specifically to the sensor being faulty rather than the cooling system itself. The evaporator sensor controls defrost cycle timing — a failed sensor leads to evaporator ice blockage over time.
Common Causes
- Evaporator sensor NTC failed after long-term exposure to defrost cycles
- Sensor connector corroded or disconnected behind the evaporator cover
- Ice buildup physically dislodging the sensor from its clip mount
What You Can Try
Perform a manual defrost if ice buildup is suspected. If E05/E06 returns after defrost, the sensor requires professional replacement — accessing the evaporator requires removing the interior back panel and is not a user-serviceable repair.
E20
Power and Display Module Communication Failure
Wiring or communication fault between power module and display
What This Means
Confirmed by Thermador Appliance Repair Service: E20 indicates the power module and display module are not communicating. This is most likely a wiring issue between the two modules. Thermador's service documentation strongly recommends professional diagnosis for E20 — attempting to trace the wiring without proper tools risks further damage.
Common Causes
- Wiring harness between power board and display board loose or damaged
- Power board or display board failed
- Communication connector corroded
What You Can Try
Unplug the refrigerator for 5 minutes and restore power. If E20 returns, no further customer troubleshooting is recommended. Contact Thermador Customer Support at 1-800-735-4328 — the wiring harness or control boards require professional inspection and diagnosis.
Water Filter alert
Water Filter Replacement Required
Filter life expired — press LIGHT/FILTER + ICE simultaneously for 3 seconds to reset
What This Means
Thermador's official refrigerator troubleshooting page confirms: the water filter symbol flashes when the filter needs to be replaced. After replacement, on certain models the symbol will continue to flash until the LIGHT/FILTER button and ICE button are pressed simultaneously for 3 seconds — this resets the filter life counter.
Common Causes
- Filter life counter reached 6 months or usage threshold
- New filter installed but reset button sequence not performed
What You Can Try
Replace the water filter — ensure it is fully rotated and seated with the lines on the filter cap aligned with the compartment lines. Then press LIGHT/FILTER + ICE simultaneously for 3 seconds to reset the filter indicator. Use only genuine Thermador-approved filters — counterfeit filters can fail to seal correctly and cause water damage. Purchase from the Thermador Accessories Store.
Microwave & Speed Oven
Built-in microwave and speed oven error codes for MBES, MCES, and MEDMC series models. Verified against Thermador USA official microwave error code support page, Thermador troubleshooting documentation, and field service reports.
E+NUM
General Electronic Fault
E code with phone number on display — internal electronic fault detected
What This Means
Thermador's official microwave and speed oven error code page confirms: when "E" and a number appear on the display along with a phone number, the microwave has detected an internal electronic fault. The specific number identifies the affected subsystem. The appliance may lock out all functions until the fault is addressed.
Common Causes
- Main control board failure — component-level fault on the PCB
- Sensor communication error between the control board and internal sensors
- Power surge or electrical event damaging the control electronics
What You Can Try
Note the exact error code shown on the display. Disconnect the appliance from the power supply by switching off the fuse or circuit breaker. Wait 30 seconds, then restore power. If the code was a one-off power fluctuation event, it will clear. If the error code returns, call Thermador Customer Support at 1-800-735-4328 and provide the exact code for diagnosis.
E11
Control Panel / Touchpad Fault
Control panel communication error — clean panel and power cycle
What This Means
Thermador's official microwave error code page confirms: E11 appearing with a phone number indicates a control panel fault. This is often caused by moisture, grease, or residue on the touchpad surface creating false inputs or blocking communication between the touchpad and the control board.
Common Causes
- Moisture or grease buildup on the control panel surface causing false touch inputs
- Steam condensation from cooking affecting the touchpad membrane
- Touchpad ribbon cable connector loose or corroded
- Touchpad membrane failure requiring replacement
What You Can Try
Per Thermador's official instructions: clean the control panel with a dry cloth to remove any moisture or grease. Disconnect the appliance from the power supply by switching off the fuse or breaker, wait 10 seconds, then restore power. If E11 clears, the issue was surface contamination. If E11 returns after cleaning and reset, the touchpad or control board requires professional service. Call Thermador at 1-800-735-4328.
E1006
Main Control Board Failure
Control board communication fault — microwave stops heating or shuts down mid-cycle
What This Means
E1006 on Thermador built-in microwaves (MCES and MBES series) indicates a communication failure between the power module and main control board. Field service reports and technician documentation confirm this code typically points to a defective main control board. The microwave may stop heating mid-cycle, shut down after a few seconds, or refuse to start entirely.
Common Causes
- Main control board component failure — known issue on MCES/MBES series
- Wiring harness or ribbon cable between power board and main board damaged
- Prior arcing or sparking event damaging control board circuits
What You Can Try
Switch off the circuit breaker for 10 minutes, then restore power. If the code clears, test by heating a cup of water for one minute. If the microwave shuts down mid-cycle or E1006 returns, the main control board requires professional replacement. The microwave must be dismounted and disassembled to access the board — this is not a DIY repair. Contact Thermador at 1-800-735-4328.
E1007
Sensor / Control Board Communication Fault
Sensor malfunction or board communication error — intermittent or persistent failure
What This Means
E1007 on Thermador built-in microwaves (MBES/02 and similar models) indicates a sensor malfunction or communication fault between internal sensors and the control board. Field technician reports confirm this code may temporarily clear with a breaker reset but consistently returns, indicating an underlying hardware failure rather than a transient glitch.
Common Causes
- Thermal sensor failure — sensor providing incorrect readings to the control board
- Control board fault — sensor communication circuit damaged
- Loose wiring connections between the sensor assembly and control board
- Overheating due to blocked ventilation causing sensor readings to go out of range
What You Can Try
Unplug the microwave or switch off the circuit breaker for 5 minutes. Restore power and test with a brief heating cycle. Ensure adequate ventilation around the microwave — check that no items in the cabinet above or below are blocking the cooling fan. If E1007 returns, the sensor assembly or control board requires professional diagnosis and likely replacement. Contact Thermador at 1-800-735-4328.
NO
HEAT
HEAT
Microwave Not Heating Food
Unit runs but food stays cold — magnetron, diode, or high-voltage circuit failure
What This Means
The microwave appears to operate normally — display works, turntable rotates, fan runs — but food does not heat. This is a high-voltage circuit failure. The magnetron, diode, capacitor, or transformer in the high-voltage system has failed. Thermador microwaves store lethal voltage in the high-voltage capacitor even after being unplugged — internal high-voltage component repair must be performed by a licensed technician only.
Common Causes
- High-voltage diode burned out — most common cause; prevents magnetron from receiving power
- Magnetron failed — end of life or damaged by arcing event
- High-voltage capacitor burned out — entire HV circuit stops functioning
- Door switch not fully engaging — microwave runs fan but does not activate magnetron
What You Can Try
WARNING: Thermador microwaves store thousands of volts in the high-voltage capacitor even when unplugged. Do not attempt to open the cabinet or test high-voltage components yourself. Press CLEAR/OFF twice, then retry heating a cup of water for 60 seconds. If the water is not warm, the high-voltage circuit has failed. Schedule a service visit with an authorized Thermador technician. Call 1-800-735-4328.
SPARK
ARC
ARC
Sparking or Arcing Inside Cavity
Visible sparks during operation — waveguide cover, interior paint, or magnetron fault
What This Means
Sparking or arcing inside the microwave cavity is a serious issue that can damage the magnetron and waveguide if not addressed. The most common cause is a damaged or food-contaminated waveguide cover — the mica panel on the ceiling or side wall of the cavity. Continued operation during arcing can destroy the magnetron and lead to control board failure and error codes like E1006.
Common Causes
- Waveguide cover (mica panel) burned, cracked, or contaminated with food splatter — most common cause
- Interior paint chipped exposing bare metal — exposed metal arcs during operation
- Metal object or foil accidentally left in the cavity
- Magnetron damaged and arcing internally behind the waveguide
- Door switch shorted — arcing in the cabinet area behind the control panel
What You Can Try
Stop the microwave immediately if you see sparks. Remove any metal objects or foil from the cavity. Inspect the waveguide cover (mica panel on the ceiling or upper side wall) for burn marks, discoloration, or food buildup. If the cover is damaged, it can be replaced — order the correct part for your model from the Thermador Accessories Store. Check the interior walls for chipped paint and touch up with microwave-safe cavity paint. If sparking occurs behind the waveguide or in the cabinet area, call Thermador at 1-800-735-4328 — do not continue using the unit.
AUTO
OFF
OFF
Microwave Shuts Off After a Few Seconds
Unit starts but stops within seconds — door switch, thermal fuse, or magnetron fault
What This Means
The microwave starts a cooking cycle but shuts itself off after a few seconds. This indicates the control board detects that the magnetron is not drawing power correctly and shuts down as a safety measure. On Thermador models with inverter boards (instead of a traditional diode/capacitor), this is a common symptom pattern. If the convection mode still works but microwave mode does not, the fault is isolated to the microwave high-voltage circuit.
Common Causes
- Door switch not fully engaging — most common cause; switch passes initial check but fails under load
- Magnetron defective — not drawing correct power, triggering safety shutdown
- Inverter board failure — not supplying correct voltage to the magnetron
- Thermal fuse or thermoprotector tripped from overheating — cuts power to magnetron
What You Can Try
Ensure the door closes fully and the latch clicks firmly into place. Check for debris or food particles in the door seal area. Press CLEAR/OFF twice and retry. If the problem persists, all internal components (door switches, inverter board, magnetron) must be inspected by a licensed technician — Thermador microwaves store lethal voltage even when unplugged. Contact Thermador at 1-800-735-4328 to schedule a service visit.
NO
START
START
Microwave Display On But Won't Start
Display active, buttons respond, but microwave does not start cooking
What This Means
Thermador's official troubleshooting page covers this condition: the microwave display is on and appears functional, but the unit does not begin cooking when START is pressed. This is often a door-related safety interlock issue rather than a control board failure. Thermador microwaves have three to four door switches that must all confirm the door is sealed before the magnetron will activate.
Common Causes
- Door not fully closed — latch not engaging the interlock switches
- Packing material, food debris, or residue stuck to the door seal
- Door seal or hinge damaged — preventing full closure
- Software glitch after power interruption — clock shows 00:00
What You Can Try
Per Thermador's official troubleshooting instructions: ensure the door is completely closed. Check the door seal for any packing material, food debris, or damage. Inspect the door for visible damage — if damaged, schedule a service visit. Press CLEAR/OFF twice and re-enter cooking instructions. If there was a power outage (display shows 00:00), unplug for 10 seconds, plug back in, reset the clock, and retry. If the microwave still won't start, a door switch has likely failed — call Thermador at 1-800-735-4328.