As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT ENGINE BLEED OFF AND L PACK OFF EICAS MSG AFTER BLOCKING OUT. A/C RETURNED TO THE GATE (BTB) AND MTX GROUNDED A/C , TROUBLE SHOT AND REMOVED AND REPLACED L/H PRSOV IAW AMM 36-11-09, A/C REMAINS NO ETOPS. OPS CHECKS GOOD AND ENGINE IDLE GOOD IAW AMM 71-00-00. RETURNED A/C TO SERVICE.