Is your Standby Power switch in AUTO? I used to see this message on the real aircraft when doing Standby Power checks on 747-400's with Alternate EFIS switches. i.e. with the Standby Power switch in BAT, the EFIS CONTROL R message should appear (If the Alternate EFIS switch is in the Captain's position).
(EDIT) I can't recall if I had to manually de-select the EFIS CP on the CDU Menu page or whether it returned to normal after the Standby Power checks were completed.
Cheers
John H Watson