Thermador Legacy Oven E10 on CT/CMT Models with Dreefs Control: Checksum Error

What E10 means

E10 on an older Thermador CT or CMT oven with a Dreefs control means the control board failed its own data check. The second page of the service document calls it a checksum error and says to replace the Dreefs board. All heat turns off while the microwave on combination models is unaffected, and the message stays on the display until the board is repaired and the oven is powered back up.

Usual causes of E10

Checksum error in the control board memory
Defective Dreefs control board, the replacement the source specifies

✓ A safe check worth trying

1. Put the selector at OFF. 2. A light counterclockwise tweak should stop any flashing or beeping. 3. If you have a combination model, you may still try the microwave section, since the source says it is not affected. 4. Leave the oven side off, and call us if E10 remains on the display.

! Why you should stop here

A checksum error means the board's own memory is suspect, so repeated resets prove nothing
Board replacement is a technician job with live power nearby
We quote legacy board work in writing and confirm it 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

F12F12 on a Legacy Thermador C-Series Oven: Vcc Lift-Off on the Power/Relay Board F50Older C/CM-Series Thermador Wall Oven F50: Upper Door Signal Shorted Low F1Older SC/SM-Series Thermador Wall Oven F1: Element Supervisor Enabled F13Thermador C/CM/CJ Wall Oven Code F13: Power Board Not Calibrated, Air Switch Check F51F51 on an Older Thermador Wall Oven (C/CM-Series): Upper Door Stuck Unlocked F2F2 on an Older Thermador Wall Oven (SC, SCD, SM, SMW): Temperature or Door Light During Self-Clean F14Thermador Older C-Series Oven, Control Display EEPROM Error F14 F52Thermador Wall Oven F52 in the Legacy C/CM Family: Upper Door Reads Locked and Open

E10E10 questions

What does checksum error mean in plain words?

The control stores settings and checks them against a stored total. If they do not match, it assumes the data is damaged and shuts the oven side down rather than risk wrong behavior.

Why does the microwave still work?

The source says the microwave is not affected by E10, so only the oven heat goes off. We still advise having the whole unit checked, since both share the same cabinet and control.

Will unplugging the oven clear E10?

Cutting power may clear the screen briefly, but the source says the error stays until repaired. If it returns, the board needs service, which we can quote in writing.