Yes I see that now. the scenario I was 'playing' with in the sim was a DMC2 fail with a subsequent AC1. This means you lose all screens until the ACESS feed selected. Since no ECAM couldn't look at electrical config (which would have answered the question). Very scary scenario since DMC2 in flight is a pretty innocuous failure but then with an AC1 you lose pretty much everything and no clues to get you out of stum (just an amber on the ACESS feed being perhaps a clue) unless you had looked at the MEL which warns of this failure and advises on the action. I cannot understand why airbus do not have an automatic transfer of the ACESS or at least put the drill for this in the QRH since no ECAM.
Anyway, that answers my question, many thanks.