Thermador Oven Error Code E240: How to Fix It

Q: What does error code E240 mean on a Thermador oven?

Error code E240 on a Thermador oven means the control board detected that the oven door was open at the beginning of a cooking or self-clean cycle. The oven will not heat until the door is confirmed to be properly closed and latched. This is a safety feature to prevent heat from escaping or causing burns.

Q: Can I still use my Thermador oven if it shows E240?

No, the oven will not start a heating cycle while error E240 is active. The error must be resolved before the oven can operate. If the door appears physically closed but the error persists, there is likely a faulty door latch switch or latch assembly that needs to be inspected or replaced.

Q: How do I reset a Thermador oven error code E240?

To reset the E240 error, press the Cancel or Off button on the control panel, then switch off the oven at the circuit breaker for 60 seconds before turning it back on. If the underlying cause (such as a faulty latch switch or obstructed door) is not fixed, the error will return when you attempt to start a new cycle.

Q: How much does it cost to fix Thermador oven error E240?

If the fix is a replacement door gasket or door latch switch, parts typically cost between $20 and $80 depending on your Thermador model, making it an affordable DIY repair. If the door hinges or latch motor assembly need replacing, parts can range from $50 to $200. A professional service call adds $100 to $250 in labor costs on average.

Q: Why does my Thermador oven say the door is open when it is clearly closed?

If your Thermador oven shows E240 but the door appears fully closed, the most common causes are a faulty door latch micro switch that is no longer signaling correctly to the control board, a worn door gasket preventing a flush seal, misaligned door hinges causing the latch not to engage fully, or a loose wiring connection between the latch switch and control board. Testing the door latch switch with a multimeter is the best next step.

Abstract

The Thermador oven error code E240 means the oven detected that its door was open at the start of a cooking or self-clean cycle, preventing the appliance from operating safely. This is a protective feature designed to stop the oven from heating when the door isn't properly closed and latched. In most cases, the fix involves checking the door latch, hinge, or door latch switch — and many homeowners can resolve this without a service call.