Legacy Thermador 30-Inch Range Displaying F3: Open Oven Sensor

What F3 means

An open oven sensor is what F3 means on a legacy ESC30 or GSC30 range: the control sees no complete circuit from the temperature probe, so it cannot read cavity heat. The legacy notes point at the sensor itself or a weak contact in the molex connector, using the same checks as F2. Newer Thermador ovens use F3 differently.

Usual causes of F3

Bad oven sensor
Poor contact in the molex connector

✓ A safe check worth trying

1. Turn the oven off and let it cool. 2. Do not tug on the sensor inside the cavity. 3. Restore power at the breaker after a short pause. 4. If F3 appears again, call us; we test sensor resistance with a meter and check the connector contacts.

! Why you should stop here

The sensor and its connector are tested with a meter.
An intermittent connection can come and go, which makes guessing unreliable.
You get the findings and a written price before we replace anything.

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 Range codes

E6Thermador PDR/PRG Range E6, Blue Lights 3-then-2: Over Temperature While Cooking F3Legacy RDF/REF 30-Inch Range F3: Open or Shorted Oven Sensor E7Cleaning Cycle Stopped by E7 on a Legacy Thermador Pro-Harmony Range (Code 23) E7010Thermador Induction Range Cooktop E7010: Wi-Fi or Hood Connection Lost E9Legacy Thermador Range E9: No Cooling Fans, Blue-Light Code 43 E9000 / E9010Thermador Induction Range Cooktop E9000 / E9010: Supply Voltage Out of Range E11Older Thermador Pro-Harmony Range E11 and Light Code 44: Door Latch Problem U400Thermador Induction Range Cooktop U400: Supply Voltage Out of Range

F3F3 questions

How is F3 different from F4?

F3 is an open sensor and F4 is a shorted one. Both lead to the same group of sensor checks, but they suggest different failures, so the exact code helps.

Could the connector be the whole problem?

Yes. The legacy document lists a poor contact in the molex connector alongside a bad sensor, and we check both before recommending a part. Neither is guessed at.

Will the oven bake at all?

We would not rely on it. Without a temperature reading the control cannot hold an accurate setting, so wait for the check before cooking anything important.