As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SJC-ON FLIGHT 2571 RETURNED TO FIELD DUE TO LEFT BLEED DUCT WARNING MESSAGE WITH AURAL MESSAGE. MESSAGE REMAINED ON AFTER 60 SECONDS. AIRCRAFT LANDED WITHOUT INCIDENT. INTEROGATED MDC AND FOUND LEFT BLEED LOOP B OPEN CURCUIT MT138. PERFORMED CONTINUITY CHECK OF LEFT BLEED LOOP AT MT138,MT140,MT203 AND MT142. NO PARTS REPLACED. OPERATIONAL CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.