Thermador Oven Error Code E122

Error code E122 on a Thermador oven indicates that the meat probe sensor circuit for the upper or single cavity (Cavity 1) has detected a temperature reading that is either excessively high or is exhibiting a short circuit condition. The meat probe is a temperature-sensing accessory inserted into food during cooking, and it connects to the oven through a dedicated receptacle typically located inside the cavity wall. The oven's control board continuously monitors the resistance signal from the probe circuit, and when that signal falls outside the expected range, the E122 code is triggered to protect the appliance and ensure accurate cooking results.

The two root causes behind this code are closely related. A shorted probe circuit occurs when the probe's internal resistance drops abnormally low, often due to a damaged probe tip, kinked or burned cable, or moisture intrusion into the probe body. A temperature-too-high reading can result from the same short condition, since a resistance drop mimics an artificially elevated temperature signal at the control board. In both cases, the probe receptacle and its connecting harness are the first components to inspect, as damaged pins, corrosion, or loose connections at the receptacle jack are frequent culprits.

If no probe is connected to the oven but the code still appears, a fault within the receptacle itself or along the harness wiring back to the control board is likely. Technicians should inspect the receptacle for bent or corroded pins, check the harness for chafing or heat damage near the cavity liner, and verify continuity and resistance through the probe circuit. A functional meat probe typically presents a specific resistance value at room temperature, so measuring the probe with a multimeter can quickly confirm whether the probe itself is defective.