F09
What code F09 means on a Bosch washing machines, what causes it, and which part to check first.
● SEVERITY: HIGH
Bosch F09 means: Heater relay fault relay controlling the heating element. The documented cause is: Relay on control board failed in open or closed position.
What F09 means
Heater relay fault relay controlling the heating element
The display shows F09 and the machine stops until the fault is cleared.
What the technical documentation says
Causes documented in the technical source published by whitegoodshelp.co.uk
| DOCUMENTED CAUSE OR CHECK |
|---|
| Relay on control board failed in open or closed position |
Replacement parts
Tools you'll need
Before you open anything
Unplug the machine and close the water tap before removing any panel. Water and mains electricity sit centimetres apart inside a washing machine. If the drum still holds water, drain it from the filter first — it can be scalding.
What to check, in order
From the quickest check to the one that needs a technician.
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Frequently asked questions
What does F09 mean on a Bosch?
Heater relay fault relay controlling the heating element The documented cause is: Relay on control board failed in open or closed position.
Can I fix F09 myself?
It depends on the part involved: Relay on control board failed in open or closed position. Clearing a filter or straightening a hose is within reach of anyone; anything behind a panel means mains electricity and water together — that is a job for a technician.
Does Bosch use other codes on this appliance?
Yes: we document 20 other codes for Bosch on this washing machines. They are listed at the bottom of this page, each with its own meaning.
Does the same code mean the same thing on other brands?
Often not. The same two characters can point to completely different faults depending on the manufacturer — always check the page for your own brand.