On the covered Thermador Masterpiece wall oven, E201 or E204 means a failure of the lower oven temperature sensor. First, cut power and check the lower sensor's harness. Then: fix loose connectors or a damaged harness, then measure the sensor: 1,080 ohms at about 70 degrees is healthy. A sensor that measures off is replaced, and with a good sensor and harness the control board is replaced.
Differential
Likely causes of “Thermador Masterpiece wall oven code E201 or E204”, and how to tell them apart
- 1
The lower oven temperature sensor has failed
What separates it The lower oven does not heat properly or shuts down
How to confirm Cut power and check the lower sensor's harness
- 2
A loose connector or damaged harness
What separates it The code came after the oven was serviced
How to confirm Fix loose connectors and replace a damaged harness
- 3
A sensor that measures off
What separates it It does not read about 1,080 ohms at about 70 degrees
How to confirm Replace the sensor
- 4
A control board that does not read a good sensor
What separates it Sensor and harness are fine
How to confirm Replace the control board
- 5
A sensor probe that is bent or touching the wall
What separates it The probe was knocked during cleaning
How to confirm Straighten it clear of the wall
Before you touch a setting
Record this first — changing settings destroys the evidence
- Whether the code is E201 or E204
- Whether the lower oven heats
- The sensor's resistance reading
- The model number
Try in this order
0 of 8 completedWhat to do first
ReversibleCut power and check the lower sensor's harness.
Correct only the documented fault domain
ReversibleFix loose connectors or a damaged harness, then measure the sensor: 1,080 ohms at about 70 degrees is healthy. A sensor that measures off is replaced, and with a good sensor and harness the control board is replaced.
Cut power at the breaker
ReversibleA wall oven is hard-wired, so switch it off at its breaker and let the oven cool before you touch anything inside.
Check the lower sensor's harness
ReversibleLook at the wiring that runs to the lower oven temperature sensor for loose connectors, pinched wires and burnt insulation.
Fix loose connectors and damaged harnesses
ReversibleThe table says to fix loose connectors and replace a harness that is damaged, since a poor connection can read as a failed sensor.
Measure the sensor
ReversibleWith a multimeter set to ohms, measure the sensor at about 70 degrees Fahrenheit. A healthy sensor reads about 1,080 ohms.
Replace a sensor that measures off
ReversibleA sensor that reads far from 1,080 ohms is replaced with one of the right part number for your oven.
Replace the control board last
ReversibleWith a good sensor and a good harness, the table says the control board is the part to replace.
Model-specific
What is true of this model and not of its siblings
- Parts involved
- The temperature sensor, its harness and the control board.
- Source
- Sears PartsDirect's table for the Thermador Masterpiece wall oven.
- What the sensor does
- The lower oven sensor tells the control how hot the cavity is, and the control switches the elements on and off to hold the temperature you set.
- Upper and lower cavities
- A double wall oven has a separate sensor in each cavity, so a code for the lower oven does not affect the upper one. You can often keep using the upper oven while you arrange the repair.
Stop boundary
When this stops being a self-service repair
- !With a good sensor and harness, replace the control board
- !Cut power before touching any wiring
- !Replace the sensor only after it has been measured
Evidence ledger
Sources behind this answer
Exact questions
Common questions
What does E201 or E204 mean on a Thermador Masterpiece wall oven?+
a failure of the lower oven temperature sensor.
What should the sensor read?+
1,080 ohms at about 70 degrees Fahrenheit.
Is the sensor costly?+
It is a modest part.
Can I test it myself?+
With power off and a multimeter, yes.
Are both codes the same?+
Yes, they are listed together.
Can I keep using the upper oven?+
Often yes, since each cavity has its own sensor, but check the manual for your model.
Why is 1,080 ohms the target?+
It is the resistance of a healthy sensor at about 70 degrees Fahrenheit, and it rises as the sensor warms.