As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FLIGHT 3906 DURING CLIMB THE CREW RECEIVED AN EICAS WARNING FOR NR 2 BLEED LEAK. THE CREW ELECTED TO RETURN TO ORD AND LANDED WITHOUT INCIDENT. THE AIRCRAFT WAS REMOVED FROM SERVICE. REMOVED AND REPLACED THE AIR BLEED LINE O-RING AT JOINT NR 16 (UNDER CARGO FLOOR PANEL 272BF) IAW EMB 145 AMM 36-11-10. THE OPERATIONAL CHECK WAS GOOD. THE AIRCRAFT WAS RETURNED TO SERVICE.