Asko Dishwasher F9 Error: Diverter valve fault
Asko dishwasher F9 error is a common issue reported by Asko appliance owners. What Does Error Code F9 Mean on an Asko Dishwasher? Error code F9 on Asko dishwashers — particularly D5000 and DBI series models that use alternating spray arm systems — indicates the diverter valve has failed to switch correctly. Asko uses a […]
No
DIY Fixable
From $160
Typical Repair Cost
45-90 min
Pro Repair Time
Quick Assessment
Answer to continue safely
Is it safe to keep using?
No. With the diverter fault active, at least one tier of the dishwasher will receive no spray coverage, resulting in unwashed dishes. The cycle may also not complete.
Can I reset the code?
Yes. Power cycling clears F9. After a descaling cycle the fault may not return if scale was the cause. A mechanically failed valve will trigger F9 consistently on the next wash cycle.
When to stop immediately?
Stop if you notice: F9 returns on every cycle after descaling and spray arm cleaning, No clicking sound from the diverter valve area is heard at all during the main wash.
Symptoms You May Notice
Upper or lower rack items consistently come out unwashed
Because the diverter is stuck routing water to only one spray arm circuit, items in the rack served by the inactive arm receive no spray pressure and remain dirty.
Cycle halts with F9 during the main wash phase
The fault typically occurs during the first main wash when the controller attempts to switch the diverter and receives no position confirmation from the valve sensor.
A clicking or grinding sound from the sump during the wash cycle
The diverter valve motor may attempt multiple times to drive the valve to its target position, producing audible clicking or grinding before the fault is logged.
F9 appears intermittently rather than on every cycle
Partial limescale restriction on the valve can cause it to succeed on some cycles and fail on others, producing an intermittent fault pattern before the problem becomes permanent.
Possible Causes
Limescale jamming the diverter valve
Mineral scale has built up in the valve housing or on the valve impeller, increasing friction to the point where the small valve motor cannot overcome it.
DIY PossibleFailed diverter valve motor
The small electric motor driving the diverter valve has burned out or its gearbox has stripped, preventing the valve from moving at all.
Requires ProfessionalBlocked or damaged spray arms increasing back-pressure
Severely blocked spray arm nozzles create excessive hydraulic back-pressure that prevents the diverter from switching, causing F9 as a secondary fault.
DIY PossibleSafe Checks You Can Do
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1
Run a descaling cycle
Add dishwasher descaler to the detergent tray and run the hottest available program with an empty machine. Citric acid solutions are particularly effective at dissolving the mineral deposits that restrict diverter valve movement.
A second descaling cycle immediately after the first doubles the effectiveness in machines that have not been descaled in over a year.
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2
Clean and test the spray arms
Remove and clean both spray arms as described in the F5 safe checks. Confirm both spin freely and all nozzles are clear. Excessive nozzle blockage creates back-pressure that can prevent the diverter valve from actuating.
Use a toothpick or cocktail stick to clear individual blocked nozzles — avoid using sharp metal tools that can enlarge the hole.
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3
Reset and run a normal cycle
Power cycle the machine (off for 60 seconds), then run a Normal wash with a light load. Listen at the start of the main wash for a clicking sound from the sump area — this is normal and indicates the diverter is actuating. The absence of this sound while F9 appears confirms a mechanical valve fault.
On D5000 series models, the diverter switches approximately every 90 seconds during the main wash — you should hear a periodic faint click.
When to Call a Professional
Contact a qualified technician if:
- Diverter valve motor shows open-circuit or incorrect resistance on electrical testing
- The valve housing is cracked or the impeller is visibly damaged when accessed from the sump
- F9 returns after diverter valve replacement, indicating a control board output fault
Need Professional Help?
Find qualified technicians in your area for proper diagnostics and repair.
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