The short answer
F8 is a safety timer rather than a fault: the table records that the cooking zone ran continuously for an extended period without interaction, so the automatic time limitation was triggered. The appliance switched the zone off because nobody had touched it. Adjust the setting and it carries on as normal.
Code table
Reference| code | meaning | owner-checkable |
|---|---|---|
| F8 | The cooking zone has been operating continuously for an extended period of time without interaction. The automatic time limitation has been triggered. | yes |
| F6 | The cooking zone has overheated. It has switched off to protect the work surface. | see page |
| U1 | Incorrect input voltage, not within normal working limits. | see page |
What you observe
- A zone switches off by itself after a long time on — Exactly what the limit is designed to do.
- It happens on unattended simmering — Long, low cooking is the usual way to meet this limit.
- The zone restarts immediately when touched — The clearest evidence that nothing has failed.
- NEAR MISS — the zone cuts out after a few minutes — A short cutout is a thermal protection, not the time limit, and it has its own code.
Likeliest causes first
- Genuinely unattended cooking — First and almost always: a stock, a stew or a slow simmer left alone for hours is the exact case the limit exists for.
- A setting left on after cooking finished — Second: a zone left at a low setting by mistake reaches the limit hours later and switches itself off, which is the feature working.
- Controls that were touched but not registered — Last: a wet or greasy touch surface may not register the interaction that would have reset the timer.
Check in this order
- Check how long the zone had been running — A long unattended period confirms the limit rather than a fault.
- Restart the zone and confirm it heats normally — Immediate normal operation means nothing is broken.
- Wipe the control surface if touches are being missed — A control that does not register your input cannot reset its own timer.
Owner-safe steps
- Touch the controls and reselect the power level — The limit clears on interaction; there is nothing else to do.
About 5 min
- Adjust the setting occasionally during long cooking — Any interaction restarts the timer, so a single touch each hour is enough.
About 5 min
- STOP HERE — there is no part and no repair here — The limit is a designed protection and cannot be disabled.
Safety first
Safety
Unplug the appliance or switch off its breaker before removing any panel — a capacitor can hold a charge after the power is off. A cooktop holds charge in its filter capacitors after the supply is cut, and the glass cracks if it is levered. Work only with the surface cold and the breaker off.
When to call
Call only if a zone hits the limit after a short period, or if the controls stop registering touches altogether — the first would mean the timer is mis-measuring and the second is a control fault. Neither is common. In every other case this code is the appliance protecting a kitchen from an unattended hob, and there is nothing to repair.
Neighbouring codes — F6 and U1 appear beside F8 in the table and are recorded against different hardware — different questions with different answers. A shared prefix on this brand is not a shared fault.
What this page does not cover
This page is written for the Bosch cooktop class rather than for one model line, and F8 is read exactly as the shared table records it. If your family or model has its own page, that page is the more specific answer and it is linked below — go there first when your model is named. Left out deliberately: connector positions, wiring colours and part numbers, which are family-specific.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
