As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ACFT RTB AFTER CREW REPORTED YSM AND F/O DISPLAY TRU STATUS MESSAGES. CREW LEFT RUNWAY AND RETURNED TO GATE IN ORDER TO ATTEMPT RESET AND THEN PLACE ITEMS ON FLIGHT CREW PLACARD AS PER MCC TLX. THIS MSG COULD APPEAR IF ACFT ON BATTERY POWER ONLY FOR 1 MIN. ACFT DOWN POWERED MCDP MSG CLEARED AND STS M CLEARED. MCO AND PLACARD REMOVED.