As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 1 ENGINE BLEED VALVE FAILED TO OPEN WHEN SWITCH IS DEPRESSED. REPLACED CARD BLEED AIR CONTROL AND REPLACED PRSOV, NO HELP. REPLACED LT HPSOV. RAN ENG, NO HELP. REPLACED HPSOV, NO HELP. CHECKED & FOUND PRV CONTROLLER NOT OPENING. REPLACED PRV CONTROLLER. OP CHECKS OK ON RUN.