Lower CANCEL Key Shorted Low: Thermador Older C-Series Oven F23

What F23 means

F23 completes the CANCEL key group for legacy Thermador C, CM and CJ ovens: the lower oven's key reads as shorted low. The service document gives the same remedy as for F20, namely connections between the display board and touch panel, then the boards or panel themselves. The same symbol on a newer Thermador oven can mean something else, so model number comes first.

Usual causes of F23

Loose or damaged display board to touch panel connections
Display board or touch panel itself, replaced as the source allows

✓ A safe check worth trying

1. Make sure the control panel is clean, dry and free of tape or magnets. 2. Turn off power at the breaker. 3. Restore it after three minutes and check the display. 4. If F23 appears again, jot down which oven you were using and call us. Leave the panel itself closed.

! Why you should stop here

Each CANCEL code has the same hardware suspects, so we test connections before parts
Pulling a touch panel can crack the glass
We give a written price first, and parts are confirmed by model number

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.

→Same appliance

More Oven codes

F25Thermador Legacy C/CM/CJ Oven Displays F25: Several Touch Keys Stuck at Once F64F64 on an Older Thermador Wall Oven (C/CM-Series): Lower Cooling Fan Air Switch Not Detected FFFF on an Older Thermador Wall Oven (SC, SCD, SM, SMW): Bad Analog/Digital Converter F30Thermador C-Series Upper Oven, Sensor Shorted: F30 on C271 to CJ302 Models F70Thermador Wall Oven F70 in the Legacy C/CM Family: Lower Meat Probe Shorted F-Thermador Wall Oven F- in the Legacy SC/SM Family: Main Board Communication Error F31Thermador Legacy CM/CJ Upper Oven F31 Sensor Circuit Open F80What F80 Means on a Legacy Thermador C/CM Wall Oven: Lower Door Signal Shorted Low

F23F23 questions

How do F20, F21, F22 and F23 relate?

They are four views of the CANCEL keys: upper or lower oven, shorted high or low. The source says F21 to F23 use the same checks as F20.

Could my lower oven still bake with F23?

Possibly, but a CANCEL key you cannot trust is a safety concern if you need to stop a cycle. We suggest not relying on that oven until checked.

What will you quote?

After testing connections, we quote the specific part the evidence supports, such as the display board or the touch panel, in writing before any work.