You could read the manual.
I found one (I assume it is at least similar; you don't give the model number). This gives a number of error codes and solutions. Nothing fo rFE12 other than - rather unhelpfully: Interrupt the power supply to the hob for approx. 1 minute.
If the problem persists after reconnecting the appliance to
the power supply, please contact the Miele Service
department.
XXX, January 2016
