E23 on documented Siemens models indicates a leak or water in the base. Turn off the water supply and avoid running more cycles while the source is being checked.
Document the leak from outside
The manufacturer documentation says to shut off the faucet if a leak is suspected. Approach from a dry area; if water is around plugs or electrical connections, get help to isolate the appliance without coming into contact with it.
Check whether the moisture starts in a hose, the detergent drawer, the gasket, or under the housing. The cycle phase also matters: say whether it appears during filling, washing, or draining. Do not remove panels to locate water in the tray.
Why drying it is not enough
The floor may look dry while the source is still active or water remains in the base. Do not tilt the washer to clear the protection. The guide to external leak detection helps record the visible path, not confirm an internal repair.
If the source is not accessible or the alert persists, request service with the E-Nr and photos. Do not treat E23 as a universal instruction to replace a hose or sensor.
Containing the water protects the surroundings; the decision to wash again depends on resolving the cause.