Thermador Range Error Code F145

The F145 error code on a Thermador range indicates that the sensor inputs on the slave microcontroller have been detected in a shorted condition. In ranges that use a dual-microcontroller architecture, a primary (master) micro handles top-level control logic while a secondary (slave) micro manages specific subsystems such as oven temperature sensing, burner feedback, or safety monitoring circuits. When the slave micro detects that two or more of its sensor input lines are shorted together, it registers this fault and communicates it to the master controller, which then triggers the F145 code.

The most likely source of this fault is a failure within the Power Board, which houses the voltage regulation and signal distribution circuitry that feeds the slave microcontroller. A shorted sensor input condition can result from internal board-level shorts caused by component failure, solder bridging, or moisture and contamination on the board surface. Because these input lines converge at the Power Board before reaching the slave micro, a fault at the board level can affect multiple sensor channels simultaneously, producing exactly this type of shorted-together reading.

Diagnosis should begin with a visual inspection of the Power Board for obvious signs of damage such as burned components, discoloration, or corrosion. However, since internal component failures may not be visible, replacement of the Power Board is the recommended first diagnostic step. If the error clears after Power Board replacement, the original board was the source of the fault. If the error persists, the wiring harness between the Power Board and slave micro should be inspected for chafing, pinching, or insulation breakdown that could cause two signal lines to contact each other.