Bosch Oven F4 Error Code: Causes and Fixes
Quick answer: Sensor short circuit
What you’ll notice
Oven shows F4; temperature sensor circuit is shorted.
Bosch
Oven
Code F4
low severity
Bosch models: Bosch displays temperatures in Celsius by default; verify the °C/°F setting before diagnosing apparent temperature errors. The temperature probe connects at the rear cavity wall. The PerfectRoast meat probe (sold separately on some models) is a different connector — do not confuse it with the RTD fault sensor.
Common causes
- RTD probe wire insulation has melted and is touching the chassis
- Moisture in the connector causing a short
Step-by-step fix
- Test the probe resistance — near zero (short) confirms the fault.
- Inspect the wire for any contact with the oven cavity walls or heating element.
- Replace the temperature probe.
Tools you may need
MultimeterScrewdriver set
Prevention
- Route the probe wire away from the broil element when reinstalling.
When to stop DIY
Same as F3 — if the probe tests good, the harness or board has the fault.
FAQ
What does F4 mean on Bosch oven?
F4 usually indicates: Sensor short circuit.
Can I keep using the appliance with F4?
Use caution. Severity is low. Same as F3 — if the probe tests good, the harness or board has the fault.
How long does this fix usually take?
Typical first-pass troubleshooting takes 20–30 minutes.