As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FL 310 LT ENG BLEED OFF, A/I VALVE, LT ENG WING LT VALVE ON. REINSTATED A/I THROUGH ISOL VALVE. RT BLEED OFF. NO PRESS SOURCE. CABIN CLIMBED TO 8000FT REINSTATED LT BLEED. SAME SEQ OF EVENTS OCCURRED AT FL 240 DIVERTED TO DFW. R&R LT AND RT ENG BLEED CONFIG CARDS RAN BLEED SYS TEST PER PFHB, ALL CKS OK PRESS A/C CKS OK RAN WITH A/I ON AND OFF ALL CKS OK.