Older C/CM-Series Thermador Wall Oven F63: Wrong Lower Oven Temperature

What F63 means

On older Thermador C-series, CM-series and CJ302 ovens, F63 flags a wrong temperature in the lower oven while cooking. One documented trigger is simple: the oven was switched on while it was still above 550 F. The other is an intermittent sensor or power/relay board. A hot restart is worth ruling out before assuming a failed part.

Usual causes of F63

Power turned on while the oven was still above 550 F
Intermittent lower oven sensor
Power/relay board, when the sensor is sound

✓ A safe check worth trying

1. Power the oven down and wait until it is well below baking temperature. 2. Wait 3 minutes with power off, then restore it. 3. If F63 clears and you recently had a power interruption mid-clean, mention that to us. 4. If it returns on a cool oven, record the code and call.

! Why you should stop here

Telling a hot restart from a failing sensor needs the oven history and a meter
Intermittent sensors pass a quick test and fail later
Repeated overheating shortens the life of other oven parts

Taking off a panel yourself does not by default void a manufacturer warranty, yet it can lead to accidental damage, and some manufacturers attach their own service terms. Read your warranty paperwork, or ask us, before you decide.

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More Oven codes

F20F20 on Thermador C-Series Upper Ovens: CANCEL Key Shorted High F54Upper Latch Input Shorted: Thermador Wall Oven F54, C/CM-Series Legacy F7Legacy Thermador Wall Oven, SC/SM Series, Shows F7: Stuck Key on the Touch Panel F21Legacy Thermador CM/CJ Lower Oven Showing F21: Lower CANCEL Key Shorted High F60Legacy Thermador Wall Oven, C/CM Series, Shows F60: Lower Oven Sensor Shorted F8Reading F8 on Older Thermador SC and SM Wall Ovens (Shorted Meat Probe Circuit) F22Thermador C/CM/CJ Wall Oven F22 Upper CANCEL Key Shorted Low F61Reading F61 on Older Thermador C/CM Wall Ovens (Lower Oven Sensor Open)

F63F63 questions

What does 550 F have to do with it?

Per the source, switching the oven on while it is above 550 F can set F63. That usually happens after a power cut mid-clean, so cooling down first is the right first step.

The code went away after cooling. Is that fine?

If the cause was a hot restart, yes. If F63 returns on a cool oven, the sensor or board is suspect and we should inspect it.

Does F63 mean food will burn?

It means the control sees a temperature it does not trust. We would not cook until it clears and stays clear, since actual heat could differ from the setting.