As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK. TAKEOFF ROLL PRESSURATION WENT TO ALT WITH AUTO-FAIL LIGHT ILLUMINATED. SWITCHED TO ALTN MODE AT APPROX. 7,500 FT ALL DIGITS WENT BLANK. OUT FLOW VALVE WENT FULL CLOSED, A/C STARTED TO PRESSURIZE TO BELOW SEA LEVEL. WENT TO MANUAL TO CONTROL OVER PRESSURIZATION. REMOVED AND REPLACED CABIN PRESSURE SELECTOR PANEL PER MM.