As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ACFT HAD AN AIR TURNBACK DUE TO LEFT ENGINE BLEED OFF LIGHT ILLUMINATED DURING TAKEOFF ROLL AFTER RESETTING THE ENG BLEED SWITCH THE LIGHT EXTINGUISHED LIGHT RE-APPEARED MULTIPLE TIMES THROUGH THE FLIGHT BOTH ENGINE DUCT PRESSURES WERE EVENLY MATCHED BUT FLUCTATED BY AS MUCH 20-30 PSI. PERFORMED FIM 36-10-00, FOUND BAD PRSOV. REMOVED AND REPLACED PRSOV PER MM 36-11-09 LEAK CHECK AND OPS CHECKED IAW 36-11-00, NO DEFECTS NOTED.