The short answer
E3100 means the safety switch has detected water in the base of the dishwasher and the leakage protection system has activated, as the table records. The machine has shut itself down and will usually keep the drain pump running to clear what it found. Treat it as a leak until proven otherwise, and do not defeat the protection to get a cycle finished.
Code table
Reference| code | meaning | owner-checkable |
|---|---|---|
| E3100 | The safety switch has detected water in the base of the dishwasher. Your leakage protection system has been activated. | partly |
| E3000 | There is a flow meter failure or an issue with water flowing into the dishwasher or the filling system. | see page |
| E3200 | There is an issue with water flow into the dishwasher. The water level is too low, or water is not being pumped correctly. | see page |
What you observe
- The machine stops and the drain pump keeps running — The protection empties the base while holding the cycle.
- Damp under the machine or at the kickboard — Visible water confirms a genuine leak rather than a sensor fault.
- NEAR MISS — water in the tub that will not drain — Water inside the tub is a drain fault; this code is about water underneath it.
Likeliest causes first
- A genuine leak from a hose, seal or the tub — First, because that is what the protection is for: a door seal, a hose clip or a pump seal weeping into the base.
- Overfoaming that pushed water out of the tub — Second: too much detergent, or washing-up liquid used by mistake, floods the base through the overflow path.
- The float or its switch stuck raised — Last: the sensor itself, suspected only once the base is genuinely dry.
Check in this order
- Pull the machine out and look underneath and behind — Water on the floor or a damp trail names the leak without anything being dismantled.
- Check what detergent was used last — Washing-up liquid in a dishwasher floods the base reliably and is a surprisingly common mistake.
- Let the base dry completely before judging the sensor — A float raised by real water is not a faulty float.
Owner-safe steps
- Turn the water off at the supply tap and the power off at the breaker — Do both before moving the machine or mopping underneath it.
About 10 min
- Mop the floor and check where the water is coming from — Look at the door seal, the hose connections and the kickboard area in that order.
Tools: cloth, torchAbout 30 min
- STOP HERE — a leak inside the machine needs it opened up — Hoses, seals and the pump are under the tub with live circuits nearby.
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 dishwasher sits on a live circuit and a water supply at once: close the supply valve as well as the breaker, and expect standing water in the base of the tub.
When to call
Call as soon as the base has been emptied and the code returns, or immediately if you can see where water is escaping. Leave the supply tap closed in the meantime: this is one of the few appliance faults that damages the kitchen rather than only the appliance. Tell the technician whether you found water underneath — a dry base with the code standing points at the float, and that is a different and cheaper repair.
Neighbouring codes — E3000 and E3200 sit beside E3100 and name overlapping hardware, so most checks here carry across. Read the two meanings side by side: where they differ in the part named, the order of the checks changes with them.
What this page does not cover
Generalized information: this reads E3100 as the shared Bosch dishwasher table records it, so it covers the model lines using that table and no others. Where a page exists for your family or model line, that one is the more specific answer — start there if your model is named. Not here: wiring colours, connector positions and part numbers, which differ by family.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
