As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 6539 - BOS-EWR - DURING CRUISE, AIRCRAFT DIVERTED TO IAD DUE TO NR 2 AHRS FAILED IN FLIGHT. AIRCRAFT WENT TO GATE WITH NO FURTHER PROBLEMS. MAINTENANCE INSPECTED AND REMOVED AND REPLACED NR 2 AHRS, OPS CHECK OK. AIRCRAFT WAS RELEASED AND APPROVED FOR RETURN TO SERVICE. (M)