Miele Washer Error Code F4256

The F4256 error code on a Miele washer indicates an EFU (Electronic Fuse Unit) fault caused by an overload condition. Specifically, the EFU 235 circuit has detected that power draw has exceeded 5 kilowatts for a duration beyond what the control system considers permissible. The EFU functions as a protective monitoring module that tracks power consumption across critical circuits. When the load on that circuit remains above the 5kW threshold for too long, the EFU triggers this fault to prevent damage to wiring, heating elements, or the control electronics.

The most likely sources of this overload condition are components that draw high current, particularly the heating element circuit. A partially failed heating element can develop a low-resistance short that pulls excessive current without fully tripping a standard breaker. Similarly, a failing motor under sustained mechanical load, or a wiring fault such as a pinched or degraded harness, can cause abnormal power consumption that accumulates into an overload event over the course of a cycle.

Because this fault involves a true power threshold rather than a simple sensor reading, it typically points to a real electrical problem rather than a sensor failure. Diagnosing the root cause requires measuring resistance across the heating element, inspecting the wiring harness for damage or arcing marks, and verifying that the control board's EFU circuit itself is not defective. The fault will generally recur if the underlying draw condition is not corrected.