Miele Washer Error Code F4166

F4166 indicates a fault in the weighing or load detection system that was detected while a wash program was running. The machine monitors drum load weight to optimize water usage and spin speed, and this code appears when the control board loses a valid signal from the loading module. The fault points specifically to the connection between the EB 230 control board and the ELP 235 loading module.

It is not recommended to continue running the washer while this fault is active. The load detection system affects how the machine controls water fill levels and spin speed, so operating without a reliable reading could lead to suboptimal wash results or stress on components. Address the fault before resuming normal use.

Repair costs vary depending on the root cause. If the fix is simply reseating a connector, there may be no parts cost at all, with only a service call fee if a technician is involved, typically in the range of $75 to $150. If the ELP 235 loading module needs replacement, parts and labor combined can range from $200 to $450 or more depending on your region and the service provider.

Start by checking the plug connection between EB 230 plug 65X and ELP 235 plug N1L_ST22. Disconnect and firmly reseat both ends of the connector, then inspect the pins for corrosion or damage. If the fault returns, test the wiring harness for continuity and inspect the ELP 235 loading module and the EB 230 control board for faults.

A reset may temporarily clear the fault code, but if the underlying issue in the plug connection, wiring, or loading module is not resolved, the error will return once a new wash program is started. A reset alone is not a repair and should only be used to confirm whether the fault is intermittent or persistent.