As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE LEFT ENGINE BLEED VALVE CLOSED SHORTLY AFTER TAKEOFF, THE AIRCRAFT WOULD NOT PRESSURIZE AND FLIGHT RETURNED TO MSP. REPLACED THE LEFT REVERSE FLOW CONTROLLER VALVE AND BLEED CONFIGURATION CIRCUIT CARD. SYSTEM CHECK DURING ENGINE RUNUP WAS NORMAL.