Maytag Oven Error Code 3d12

Error code 3d12 means the control board detected an open circuit in the lower oven temperature sensor. The sensor is reading infinite resistance, which tells the board it has lost all temperature data for the lower cavity. As a result, the oven disables all cooking functions for that cavity until the fault is resolved.

Start by checking the lower oven temperature sensor for continuity using a multimeter set to the resistance or continuity mode. Disconnect the sensor leads and probe the terminals. A healthy sensor reads a finite resistance value, typically around 1080 to 1100 ohms at room temperature. An open reading means infinite resistance, and the sensor must be replaced. If the sensor tests good, inspect the wiring harness from the sensor to the control board for breaks or burned sections, and check that all connectors are seated firmly.

Disconnect power to the oven at the breaker before beginning. Locate the lower oven sensor probe at the back wall of the lower cavity and unplug its harness connector. Set a multimeter to measure resistance and probe both sensor terminals. At room temperature, a functioning sensor reads approximately 1080 to 1100 ohms. A reading of infinite ohms or OL confirms the sensor is open and needs replacement. If the sensor reads correctly, reconnect it and check the harness wiring and connectors for damage before suspecting the control board.

No. When 3d12 is active, all cook functions for the lower oven cavity are disabled by the control board. The oven will not heat because it cannot safely regulate temperature without a working sensor signal. If your unit is a double oven, the upper cavity may still function independently, but the lower oven will remain inoperable until the sensor issue is corrected.

A replacement lower oven temperature sensor typically costs between $20 and $60 for the part, and replacing it is a manageable DIY repair requiring only a screwdriver and a multimeter. If the wiring harness is damaged, harness repair or replacement can cost $30 to $80 in parts. If the control board has failed, that part generally runs $150 to $300 or more. Professional labor typically adds $100 to $200 to any of these repairs depending on your region.