As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
YEG FLIGHT NR 2315, PRESSURIZATION NEVER OCCURRED ABOVE 0.5 PSI DIFFERNTIAL. BLEED AIR OK, MANUAL PRESS WOULD NOT PRESSURIZE EITHER. MTX PERFORMED OPERATIONAL CHECK OF AUTO PRESSURIZATION CONTROL FAULT INDICATION IAW AMM TASK 21-31-00-710-802. OPS CHECKS OK. PERFORMED FUNCTIONAL TEST OF PRESSURIZATION SYSTEM IAW AMM TASK 21-31-00-720-801. OPS CHECK OK. UNABLE TO DUPLICATE FAULT. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.