Hi, thanks for using JustAnswer.com. Please remember, I do not get paid for my time and expertise until you accept. The error code F51 indicates an issue with the RPS sensor in the motor. It has been a source of trouble for the Cabrio, Bravos and Oasis machines. There has been a kit developed for the F51 trouble and comes with complete installation instructions, including pictures. It is available at the link below.
RPS Sensor Kit $62.52
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