As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS NOT DECLARED DUE TO: DURING CLIMB LEFT BLEED TRIP OFF ANNUNCIATOR ILLUMINATED, LEFT BLEED TRIP OFF ANNUNCIATOR REMAINED ILLUMINATED AFTER QRH. AIRCRAFT AIR INTERRUPTED BACK TO AND LANDED SAFELY AT ORD. REMOVED AND REPLACED NUMBER 1 (PRSOV)- PRESSURE REGULATOR AND SHUTOFF VALVE. PER MM 36-11-04, OPERTIONAL AND LEAK CHECK GOOD.