Siemens E28 dishwasher: what it means & what to check

What E28 actually means

The dishwasher's water-clarity sensor isn't giving a sensible reading, so the machine can no longer tell how dirty the water is.

Siemens dishwashers use a turbidity sensor that looks at how cloudy the wash water is and adjusts the cycle — extra rinses, longer wash, more water — to match the load. When the control board sees a reading it can't trust from that sensor, it logs E28. The usual complaint that brings it to light isn't a stopped machine but poor results: plates coming out with food still on them, and grey or dirty-looking water sitting in the tub.

What E28 looks like on a Siemens dishwasher

Most people find this page having searched for what the machine is doing rather than the code itself. On a Siemens dishwasher, E28 usually shows up as one or more of these:

Dishwasher not draining
Water left in the tub at the end of the cycle
Stops mid-cycle full of water
Standing water in the bottom
Not filling with water
No water going in
Takes for ever to fill
Stops right at the start of the cycle

Recognise any of those? That is this fault, and the rest of this page explains what causes it and what you can check yourself.

What usually causes it

Grease, limescale or food film coating the sensor so it can't see through the water
Blocked or badly clogged filters keeping dirty water circulating past the sensor
Genuine failure of the turbidity sensor itself
Wiring or connection fault between the sensor and the control board
Control board misreading the sensor signal

What you can safely check yourself

Work through these in order. Anything beyond this — panels off, testing parts, anything to do with the wiring — is an engineer's job, and not one to attempt with the machine plugged in.

Lift out the filter assembly in the base, rinse it under a hot tap and clear any food, glass or grit from the sump area before refitting it
Check the spray arms spin freely and the small holes in them aren't blocked with debris or scale
Run a hot cycle with a dishwasher cleaner or descaler to shift grease and limescale build-up inside the tub
Make sure you're not overloading or stacking dishes so they block the spray, and scrape heavy food off before loading
Switch off at the wall for a minute, then power back on to see whether the code clears

Common questions about Siemens E28

What does E28 mean on a Siemens dishwasher?

The dishwasher's water-clarity sensor isn't giving a sensible reading, so the machine can no longer tell how dirty the water is. Siemens dishwashers use a turbidity sensor that looks at how cloudy the wash water is and adjusts the cycle — extra rinses, longer wash, more water — to match the load. When the control board sees a reading it can't trust from that sensor, it logs E28. The usual complaint that brings it to light isn't a stopped machine but poor results: plates coming out with food still on them, and grey or dirty-looking water sitting in the tub.

Can I fix Siemens E28 myself?

There are 5 checks you can safely do yourself first.

Lift out the filter assembly in the base, rinse it under a hot tap and clear any food, glass or grit from the sump area before refitting it.
Check the spray arms spin freely and the small holes in them aren't blocked with debris or scale.
Run a hot cycle with a dishwasher cleaner or descaler to shift grease and limescale build-up inside the tub.
Make sure you're not overloading or stacking dishes so they block the spray, and scrape heavy food off before loading.
Switch off at the wall for a minute, then power back on to see whether the code clears.

This sometimes clears with those checks. If it comes back, it needs looking at properly.

How much does it cost to repair Siemens E28?

£66 including VAT for an engineer to come out and diagnose it, or £84 in total including VAT if it is put right on the visit and no parts are needed. Any parts needed are quoted on site before we fit them — you decide. Every repair carries a 90-day workmanship guarantee.

Tried the checks and it's still showing E28?

This sometimes clears with the checks above. If it comes back, it needs looking at properly. Then it wants someone who can open it up.

What it costs, before you call: the price is the same whatever the fault turns out to be — £66 including VAT for an engineer to come out and diagnose it, or £84 in total including VAT if it is put right on the visit and no parts are needed. Any parts needed are quoted on site before we fit them — you decide. Every repair carries a 90-day workmanship guarantee.

Our own engineers, not a call centre. We cover Nottinghamshire, Derbyshire and Leicestershire — most dishwasher faults are seen same day or next day.

Call 0115 648 0929 Book online — postcode and number is all we need

Outside our area? The explanation above still stands — take it to a local engineer and tell them the code. Knowing it saves them time and you money.

Other Siemens dishwasher codes

All Siemens fault codes and repairs →

What this looks like when it happens

Repairs we cover near you

Written by the engineers at ASAP Repairs, 0115 648 0929. We repair these machines for a living in Nottinghamshire, Derbyshire and Leicestershire.

Siemens E28 error — dishwasher