As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WITH BOTH PACKS IN AUTO AND BOTH BLEED SWITCHES ON, THE LEFT BLEED DUCT PRESSURE READS 25 PSI AND THE RIGHT READS NEAR ZERO. REPEAT ISSUE FROM PAGE 11606395. ACFT GROUNDED. IAW AMM 36-11-00-700-804 BLEED AIR TROUBLESHOOTING INDICATES BAD BLEED AIR REGULATOR. REMOVED AND REPLACED RT ENGINE IAW AMM 36-11-03-000-801/-400-801. ACCOMPLISHED GROUND VERIFICATION, OPS CHECK NORMAL WITH GROUND RUN.