Error f51 my washer is flashing f51

Cabrio F51 Fault (Stored Fault Code F51) The Cabrio's F51 fault code flashes on the washing machine's display when there is a motor rotor position sensor (RPS) failure.
Check for good contact at the control Board and at the RPS. Sometimes disconnecting and reconnecting the RPS plug connection several times will clean off corrosion that may be affecting the contacts.

Here is an earlier Fixya answer addressing the query:

Whirlpool cabrio error code f51 what does it mean

Sensor is item 20 below. Clean it.

On some machines the F51 is a slow or long drain error. Possibly a clogged filter in the drain pump or a bad pump. You did not provide enough information for me to offer any more help. I do not know the washer type, manufacturer, age, or model.

Check this site:
http://www.applianceblog.com/mainforums/threads/27512-Whirlpool-Cabrio-stopped-working-error-code-F51

and this one:
http://www.applianceblog.com/mainforums/threads/7910-Whirlpool-Cabrio-washer-F51

You will need to replace the RPS sensor. There is a kit available that will update that washer to the current design. Here is the kit to order.

Hi,

The error means that washer repeatedly quits mid-cycle. Basically, the F51 error is a rotor position sensor error.

Also check the below article for details:

http://cabriof51error.blogspot.com/

http://appliancejunk.com/forums/index.php?topic=1753.0

Thanks,

E-ware

The F51 error is a RPS (rotary position sensor) board failure where the control board looses contact with the RPS during the machines operation. The RPS uses hall effect sensors to determine the speed and direction of the drive motor, allowing the control board to constantly monitor the motors operation. Because this error is a communication error and not a mechanical error with the motor itself (that would be and F52 error) we can limit our trouble shooting to the three items that make up the RPS circuit, the control board, the wiring harness, and the RPS itself.

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check if basket turns freely. if it does replace the main board

bad main board or motor possitioner sensor.. most likely motor sensor.
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