Jura Error 2 and Jura Error 4 are the most frequent but Errors 1, 3 or 5 may sometimes show depending on the software version and the amount of thermoblocs in the machine. They all refer to the Jura thermobloc (water heater units) and temperature systems and will indicate that the Jura machines logic board is receiving a signal that is outside of expected tolerance values. In other words the sensor has failed and is either not sending a signal or sending an incorrect signal, or the thermobloc is not heating.

This may be because the thermal fused cords which supply the thermobloc with its power are designed to "blow" cutting power if the thermobloc gets too hot as a safety precaution. This in turn can often be caused by a failed sensor allowing the thermobloc to overheat.

In all these cases the first thing to do is disconnect the power from your Jura machine and allow the machine a few minutes before reconnecting the power - this will confirm if it is a hard fault or just a glitch.

Sometimes, if the machine has been exposed to low temperatures (for example), it can take a while for the thermblocs to heat up and your Jura coffee machine can see this as a fault. It has a time limit in which to heat the thermobloc to correct temperature, so starting again will often clear the issue if there is no actual damage.

If the above is unsuccessful, it is likely we will need to open your Jura coffee machine and change some parts - usually the sensor for the appropriate thermobloc (some Jura models like the Jura Z5 and Jura Z7 have two) and the fused cords. This is because if the sensor has failed it is likely to have overheated the cords to a point where they are weakened. If the fused cords have blown it was likely because the sensor allowed the thermobloc to overheat.

On rare occasions the power board which switches on and off power to the thermobloc can have a fault which stops it from cutting power to the thermobloc when temperature is reached, causing the same symptoms. This would need a new board, as once the damaged sensor and fused cords have been replaced they will be blown again.

This is the electronic ceramic valve, seen on Jura Z5, Z6, Z8, Z9, X5, J5, J6 and J9 and several other units. This valve has a motor which can often be heard whirring at start up and it is responsible for directing water and steam to different outlets and dumping waste steam pressure to the condenser block.

This error indicates that the electronic ceramic valve is not operating correctly, it can be jammed with scale, it can be leaking or have water leaking onto it causing the circuits to short out or it could just be failed.

This is a frequent issue on Jura coffee machines, mainly because it refers to the Jura Brew unit which, as you can imagine, is the heart of the machine in constant operation making the coffee.

The causes of Error 8 on the Jura coffee machines are often instantly diagnosed as brew unit failure, however in our 15 years working on Jura coffee machines we have established that the cause of the Error 8  can be any or several of a number of components.

If Error 8 is displayed, your Jura machine is informing you, that as far as its sensors are aware, the brew unit has failed to move correctly through its cycle. This can be the obvious tired and stiff brew unit or it can be the drive encoder failing to give the correct information to the logic board and sometimes the wiring harness can be damaged, so preventing correct signal from the encoder.

If a loud grinding noise precedes the error 8 then the brewer drive motor is likely to have fractured one of its mountings and if a series of loud clicks but no real movement of the brewer precedes the Error 8 then the transformer is probably failing under load and requires replacement.

There is still another possibility with the error 8 and that is that the relay on the power distribution board is sticking and not engaging power to the brewer motor.