E23 on documented Bosch washing machines indicates a leak or water in the lower tray. Turn off the supply valve and address the leak before trying to continue.
Contain without disassembling
The manufacturer documentation indicates closing the supply tap if a leak is suspected. Do this from a dry, accessible position. If there is water near electrical components, do not step in the puddle or handle the plug; ask for help to isolate the unit safely.
Observe from the outside whether the water appears at a hose joint, under the drawer, at the door, or beneath the housing. Note whether it started while filling, washing, or draining. Drying the floor makes it easier to spot new leaks, but it does not prove the source has been fixed.
Water in the base without a visible puddle
The tray can retain water internally; not seeing it on the floor does not rule out the stated condition. Do not tilt the washer to empty it or rerun programs to make E23 disappear. Consult the leak location guide only for external observations and request assistance if the warning persists.
Confirm the E-Nr: this meaning applies to documented Bosch washing machines, not to an E23 on dishwashers.
For assistance, keep track of the water location, cycle stage, and a photo of the alert without opening panels.