As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RT REV ISOLATION VALVE EICAS MESSAGE AFTER ENGINE START. AIRCRAFT RETURNED TO GATE, AIRCRAFT WAS GROUNDED. MAINTENANCE INVESTIGATED PROBLEM. OPERATIONAL CHECK OF RT REVERSER GOOD, IAW AMM 78-31-00. REV CYCLED 3X TIMES WITH NO MESSAGES. AIRCRAFT RELEASED FOR FLIGHT.