As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT PACK HIGH PRESSURE ILLUMINATED ON TAKEOFF ROLL. RAN QRH ON CLIMBOUT. PACK WOULD ONLY RESET WITH APU RUNNING. AIR RETURN, NO EMERGENCY DECLARED. C TAXIED ACFT TO RUN PAD AND PRESSURIZED BOTH PACKS FROM ENGINES IAW AMM 21-50-00-863-805. NO DEFECTS NOTED AT ALL POWER SETTINGS. AIRCRAFT OK FOR SERVICE.