As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 917 JFK-ORD, CREW DECLARED EMERGENCY AND AIRCRAFT RETURN BACK TO JFK DUE TO BLEED 2 FAIL FOLLOWED BY BLEED 1 LEAK DURING CLIMBOUT. ACCOMPLISHED TSM FOR BLEED 2 FAIL, REMOVED AND REPLACED NR 1 ENGINE PRECOOLER AS PER AMM 36-11-08 DUE FOUND LEAKING. OPS AND LEAK CHECK OK.