Thermador Range Error Code F81

F81 on a Thermador range means the control system has detected that the lower oven door is stuck in the unlocked position. The power/relay board monitors the door latch switches to confirm whether the door is locked or unlocked, and F81 is triggered when a locked state cannot be confirmed. This fault most commonly appears in relation to the self-clean cycle, which requires the door to lock before high-heat operation can proceed.

Normal baking and cooking functions may still be available, but you should not attempt to run a self-clean cycle while this fault is active. The self-clean cycle requires a confirmed locked door position to operate safely at high temperatures. Continuing to use the self-clean function without a properly functioning door latch presents a safety risk.

Repair costs depend on the failed component. If the fix involves reseating a connector or replacing a door latch switch, costs are generally in the lower range, typically between $100 and $250 including labor. If the power/relay board needs to be replaced, parts and labor costs can range from $300 to $600 or more depending on the specific model and service rates in your area.

Some steps are accessible to a knowledgeable DIYer, such as inspecting the door latch for debris, checking that wiring is not pinched, and reseating the connector at header P5 on the power/relay board. However, testing the latch switches for proper continuity and replacing the power/relay board require electrical knowledge and comfort working with appliance components. If you are not confident with these tasks, a qualified technician is recommended.

A power reset by disconnecting the range from power for a few minutes may temporarily clear the code, but if the underlying fault still exists, the error will return. The door latch switches, wiring, and header P5 connection need to be inspected and any faulty components addressed to permanently resolve F81.