As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT SYS HYD FAILURE AT FLT 290 WITH 19 QT OF FLUID AT ZERO PRESSURE. ATTEMPT TO RESTORE HYD POWER AS PER POM WITH AUX PUMP ON AND TRANSFER PUMP ON IN FLT AND STILL HAD NO PRESSURE IN THE LEFT SIDE. REPLACED LEFT ENGINE HYD PUMP. ALSO, REPLACED ALL FILTERS.