As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CLIMBOUT LEFT BLEED ZERO PRESSURE NORMAL INDICATIONS ON START AND TAXI DEBRIEF CREW, LOST OF DUCT PRESSURE AT CLIMB OUT #1 ENGINE . (LEFT DUCT ZERO 0) (RIGHT DUCT PRESSUREGHT 50 PSI). ENGINE BEEN THE SOURCE. PREFORMED PNUEMATIC HEALTH CHECK REF. AMM 36-11-00-700-801 FOUND THAT BLEED AIR REGULATOR WAS NOT COMMANDING PRSOV TO OPEN. REMOVED AND REPLACED ENG# 1 BLEED AIR REGULATOR REF. AMM 36-11-03-400-801 LEAK CHECKS GOOD. PERFORMED BLEED AIR CROSSOVER CHECK REF. AMM 36-11-00-710-801 ALL PARAMETERS IN LIMITS. OK FOR SERVICE.