Brew Unit Max Pressure error

[lifeisfun]

After removing, cleaning and re-inserting the brew group very often I see on this machine error : Brew Unit Max Pressure
This will cause wasting coffee and mess in the unit.
Next brew is just fine.
It will never happen if I first run empty before ground coffee shot.
Powder is not to fine, and machine is perfectly clean even the grinder was cleaned.

Any ideas where to start troubleshooting??

Thanks!

 

[uhrmacher]

The switch on the large gear in the gearbox is defective. Either you exchange it or you burn the contacts free. To do this, clamp an electrolytic capacitor with around 100 µF across the switch contact (observe polarity) and close and open the switch 50 times. machine switched on.

 

[lifeisfun]

The switch on the large gear in the gearbox is defective. Either you exchange it or you burn the contacts free. To do this, clamp an electrolytic capacitor with around 100 µF across the switch contact (observe polarity) and close and open the switch 50 times. machine switched on.

The speed and confidence in your answers amazes me every time!
Thank you so much !