What to check yourself
Step 1. Turn off the water supply and pull the plug
The shut-off valve is usually under the sink. Do this before anything else, because everything below involves moving the machine or reaching into it.
Water is sitting in the base of an appliance that is wired to the mains. Unplug it rather than just switching it off at the panel front.
Step 2. Ask yourself how much detergent you use
This is the check nobody starts with and it explains roughly a third of cases. Too much detergent, or rinse aid, produces foam that climbs over the sump and drips into the base tray. There is no leak at all: the machine is drowning in its own suds. If you fill the dispenser to the brim, or use pods plus a splash of extra powder, this is very likely you.
Step 3. Tilt the machine back to empty the tray
This is the trick technicians use and Bosch does not publish. Pull the machine out, tip it backwards to around forty five degrees, and hold it there for a minute. The water in the base runs out at the back, the float drops, and the error clears. Be honest with yourself about what this is: it empties the tray, it does not fix a leak. If the cause was foam, you are genuinely done. If something is dripping, the code comes back within a few cycles.
A dishwasher is heavy and awkward. Get a second person rather than doing this alone, and put a towel down for the water that comes out.
Step 4. Reset it properly, all three conditions at once
The reset only takes if the tray is dry, the float has dropped back down, and the power has been off for at least five minutes. Most people do one of the three, see the code still there, and conclude the machine is dead. Do all three together.
Step 5. Look for where the water came from
With the machine out, check the door seal along its whole length, the inlet hose and its connection, the hose clamps, and the area under the sump. A stain, a drip mark or a patch of limescale shows you the spot. If you find nothing and the code stays away after the tilt and the detergent change, it was foam.
What a technician will look at
Described so you know what you are paying for, not as steps to repeat.
Trace the leak properly
A leak that keeps coming back means a seal, a hose or the sump itself. That means dropping the base panel and running the machine while watching where the water appears, which is a job on a live appliance with the panels off.
When to call a technician
If the code returns after the tray has been emptied and you have cut back the detergent. A repeat means real water is arriving from somewhere, and it will keep arriving until it is found. Call sooner if you can see water on the floor rather than just in the tray.
What the repair costs
| Repair | Part only | Fitted by a technician |
|---|---|---|
| Cutting back the detergent, if foam was the cause | - | Free |
| Diagnosis and hose or seal replacement | - | $150 to $350 |
| Sump or tub repair | - | $300 to $550 |
A new machine of the same class runs $500 to $1,500. Once a quote passes about a third of that on an older appliance, the repair stops making sense.
Codes people confuse this with
Questions people ask
- I tilted it and the code cleared. Is it fixed?
- It is cleared, which is not the same thing. If the cause was foam from too much detergent, then yes, you are done, provided you actually change the dose. If something is leaking, the tray fills again and the code returns, usually within a handful of cycles. Treat the next two weeks as the test.
- How much detergent should I actually use?
- For a normally soiled load in average water, about half of what most people put in. One tablet or a filled main compartment is plenty; topping it up with extra powder is what starts the foam.
- There is no water under the machine. Why the error?
- The float sits in a tray inside the base of the appliance, not on your floor. It trips on water that has not escaped yet. You caught it early, which is the entire purpose of the system.
- Can I disable the leak protection to finish the dishes?
- No. It is the part standing between a failed hose and your kitchen floor, and on many models it also closes the water supply at the tap end. If it tripped, it found something.
Which machines this applies to
Applies to
Bosch dishwashers across the 100 to 800 Series and the European Serie range. Machines with newer electronics show E3100 for the same fault.
Last checked
2026-08-03