Bosch Washer Error Code E23 — AquaStop Leak Detection Activated
What this means
The E23 (or F23) error code on Bosch washing machines indicates that the AquaStop leak protection system has been activated. Water has been detected in the base tray of the machine, which triggers a safety shutoff to prevent flooding. This can be caused by a leaking internal hose, a cracked tub, a loose pump connection, or a defective AquaStop inlet hose. The washer will immediately stop all operations and lock the door when this code appears.
Alternate codes: F23
Step-by-step fix
4 stepsTurn off the water supply immediately
Close the water tap connected to the washer to stop any further water flow. Unplug the washer from power. Do not attempt to run any cycles — water in the base tray can damage electrical components if the machine is powered on.
If water is visible on the floor around the washer, mop it up immediately to prevent floor damage.
Tilt the washer to drain the base tray
Carefully tilt the washer backward about 6 inches to allow water in the base tray to drain out the front or back. Place towels to catch the water. The AquaStop float switch must drop back down before the error will clear.
Have a helper hold the washer while tilted. Do not tilt more than 45 degrees or you risk damaging the drum suspension.
Identify the leak source
With the washer unplugged and tilted forward, inspect the base tray area with a flashlight. Look for wet spots or drip trails on internal hoses, the pump housing, the tub seam, and the door boot gasket. Trace any moisture back to its source.
Common leak points on Bosch washers include the drain pump seal, the door boot clamp, and the soap dispenser to tub hose.
Check the AquaStop inlet hose
Disconnect the AquaStop hose from the water tap. Inspect the hose for damage, cracks, or a triggered safety valve (indicated by a red indicator in the transparent window). If the AquaStop has been triggered, the hose must be replaced — it cannot be reset.
A triggered AquaStop hose will completely block water flow as a safety measure. A new hose is required to restore operation.
When to call a professional
If the leak is coming from the tub seam, the outer drum bearing seal, or if you cannot identify the source, professional diagnosis is strongly recommended. Internal tub leaks can involve substantial disassembly.
Related error codes
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
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