Thermador Masterpiece and Professional electric wall ovens (ME / MED / MEM, PO / POD): quick sheet

Covers: Thermador 30-inch built-in electric wall ovens of the current Masterpiece generation: single ME301 (for example ME301WS), double MED302 (for example MED302WS), single MED301 and combination MEM301 (oven over speed/microwave, for example MEM301WS), and the matching Professional series PO301 / POD302. Older Masterpiece (SEM / SED, MES / MED with earlier suffixes) and C-series (SC / SCD) ovens share the diagnostic logic but not all parts. BSH (Bosch group) builds. Read the rating label on the oven frame (door open) for the full model and FD number.

Cross-checkedBrands: Thermador8 components

Hard-wired 240/208 V wall ovens with true convection (a rear fan with its own ring element), a hidden or exposed bake element, a broil element, self-clean with a motorized lock, Home Connect Wi-Fi, probe and SoftClose hinges. Thermador publishes no per-code meanings for these ovens: its support page says to silence the beep, reset, and call if an E-code returns, so tech diagnosis is classic oven work: elements, sensor, thermal cutout, lock, convection motor and the relay board. Doubles draw about 40 A and singles about 30 A, so supply problems and burnt terminals are real failure points.

Safety first

Turn off both legs of the breaker (30-40 A) and verify dead before any panel removal (caution).
Combination models include a microwave section with a high-voltage capacitor: do not open it unless trained and the capacitor is discharged (caution).
Wall ovens are heavy; never pull one out without support underneath.

How it works

Heat sources: a bake element under the floor, a broil element at the ceiling, and a convection ring element around the rear fan for true convection. Thermador lists a single ME301WS at 6,400 W on a 30 A circuit and a double MED302WS at 9,200 W on a 40 A circuit; a retailer lists the single's elements as bake 2,400 W, broil 3,800 W and convection 2,000 W.

Control: the user interface sends commands to a relay (power) board that switches each element, the convection motor, the cooling fan, the lights and the lock motor. A temperature sensor in the cavity closes the loop. Fault conditions show as 'E' plus a number with beeping; Thermador's guidance is press any key to stop the beep, reset, and book service if it comes back.

Protection: a high-limit thermal cutout (thermal fuse) in the cooling path removes heating power if the electronics area overheats; a failed cutout gives a dead or no-heat oven with a working display.

Self-clean: the lock motor drives the latch and switches tell the board when it is locked and unlocked. The lock will not release while the control believes the cavity is hot, and the cooling fan keeps running; on forum reports a failed sensor or a bad sensor connector at the relay board can keep the door locked after cleaning.

Combination models (MEM301) put a speed/microwave oven in the lower cavity; that section carries microwave high-voltage hazards and is caution-only work.

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Official manufacturer documentation

Always confirm values against the tech sheet for the exact model.

OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work. © 2026 OnCall Tech. Original content; not a reproduction of any manufacturer document.Generic part photos (not of this brand): Large stainless refrigerator set flush between kitchen cabinets by Alex Qian, Pexels License

Diagnostic guides for this appliance

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