All Jura machines in the series C, E, F, J, S & Z models have the same problem. The Jura recommended maintenance is insufficient or erroneous:
1- When new machine is set up, the owners click OK for use of Filter cartridges. This helps only to display reminders for replacing the filter.
2- The instruction also advises, regular use of Filters, eliminates descaling the machine. That is not accurate. Reminders for descaling are delayed or eliminated. This allows accumulation of Calcium deposits in the entire hydraulic and coffee system.
3- Cleaning tables recommended & sold by Jura do not remove Calcium deposits in the coffee/water passages. The automatic descaling method recommended by Jura also leaves the coffee side of the machine unclean. The error message in your machine is due to Calcium deposits in the Brew group, coffee outlet & the faucet dispensing coffee in the cup. I suggest all Jura machine owners should manually descale machine. Manually descaling includes use of 6 to 10 rinse cycles with descaling solution in the water tank. The error message "Clean Machine" is accurate & pointing to descaling the Brew group, coffee outlet tube and coffee dispensing faucet by using rinse cycles.

After the rinse cycles are complete, refill Descaling solution & continue descaling the rest of the machine using hot water dispensing function, until the tank is empty. Finally, give a final flushing of machine to flush out remaining descaling solution inside the machine.
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