Bosch Oven F5 Error Code: Causes and Fixes

Editorially reviewedUpdated 2026-02-20

Quick answer: Control board communication issue

What you’ll notice

Oven stops and shows F5; a communication fault between control boards has been detected.

Bosch Oven Code F5 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

  • Main control board to display/relay board communication interrupted
  • Power surge corrupted communication state
  • Ribbon cable or connector loose

Step-by-step fix

  1. Power cycle (breaker off for 5 minutes).
  2. If recurring, open the control panel and reseat the ribbon cable between boards.
  3. Inspect for burn marks.

Tools you may need

Screwdriver set

Prevention

  • Use a surge protector on the oven circuit.

When to stop DIY

Call a technician for control board replacement if the fault persists.

FAQ

What does F5 mean on Bosch oven?

F5 usually indicates: Control board communication issue.

Can I keep using the appliance with F5?

Use caution. Severity is low. Call a technician for control board replacement if the fault persists.

How long does this fix usually take?

Typical first-pass troubleshooting takes 5 minutes (reset); 30 minutes (cable check).