As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
STRONG ACRID ODOR WHEN APU RUNNING. CREW DEBRIEFED. ON ENG SHUTDOWN, RT PACK ACM FAILED AND CAUSED BURNING ODOR IN CABIN ALONG WITH ASSOCIATED STATUS MESSAGES. TESTING SHOWED RT ACM FAILED & MEL APPLIED ON LP 9971449. CONDITIONAL INSPECTION FOR SMOKE/ODOR IAW AMM DMC-B787-A-05-51-99-99A-282A-A COMPLETED. RAN PACKS, NO ODOR AFTER MEL APPLIED. OK TO CONTINUE FOR FLIGHT.