Reading F8 on Older Thermador SC and SM Wall Ovens (Shorted Meat Probe Circuit)

What F8 means

F8 on older Thermador SC, SCD, SM and SMW ovens reports a shorted meat probe. What stands out is that these models do not use a probe at all, so the reading does not come from anything you plugged in. The service document points straight to the main power/relay board as the cause and calls for it to be replaced.

Usual causes of F8

Main power/relay board that misreads the probe input

✓ A safe check worth trying

1. Power down and allow the cavity to cool. 2. Reset using OFF or the breaker for 3 minutes. 3. Check the display after restoring power. 4. If F8 returns, note it and your model number and call. There is no probe to check on these models.

! Why you should stop here

The cause sits on the main board, which requires safe board handling
Confirming it takes testing before a board is ordered
Board work is not a homeowner job on a built-in oven

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

F10Thermador C-Series Wall Oven F10 on C/CM/CJ Models: Power Board Incompatibility F34Thermador Legacy C/CM/CJ Oven F34: Upper Oven Cooling Fan Air Switch Not Detected F83Reading F83 on Older Thermador C/CM Wall Ovens (Lower Door Stuck Position) E + numberThermador POD301 and POD302 Oven E + number: Display Code With Beeping F11Thermador CM/CJ Built-In Oven F11 (Legacy C-Series): Power Board Communication Error F40Thermador Oven F40 on Older C-Series Models: Upper Meat Probe Shorted F84Thermador Wall Oven F84 on Legacy C/CM-Series Ovens: Lower Latch Input Shorted F12F12 on a Legacy Thermador C-Series Oven: Vcc Lift-Off on the Power/Relay Board

F8F8 questions

I have no meat probe. Why F8?

The oven has no probe, so the code comes from the board reading its own probe input as shorted. The source therefore points to the main power/relay board.

Is F8 serious?

It stops the oven in the legacy table we follow, rated medium. It is not a safety alarm, but the oven needs a check before it runs reliably.

Can I repair the board myself?

We do not recommend it. Boards on built-in ovens carry line voltage. A technician confirms the cause and quotes in writing first. Please keep the oven off until the visit.