As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE AIRCRAFT WOULD NOT PRESSURIZE. THE NUMBER ONE BLEED VALVE INDICATED 3 PSI. R&R #1 ENGINE BLEED AIR PRESSURE REGULATOR IAW B737 AMM 36-11-16, OPS CHECK GOOD. BLEED AIR SYSTEM LEAK CHECK GOOD IAW B737 AMM 36-11-05, PERFORMED ENGINE RUN TO IDLE, OPS CHECK GOOD IAW B737 AMM 71-00-00 NO DEFECTS NOTED