The codes Rok Dr posted relate specifically to loss of communication between ECU and the EAT ECU, so the trouble is going to be on the CANBUS lines between the two.
The P1842 is basically a follow-on fault from the loss of communications, and indicates that the signals being sent between the two ecu's.
I've attached the P1843 diagnostic flow only as the P1842 will clear up when you solve the underlying problem.
cheers
Paul

