As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT 5075, AT GATE AFTER ENGINE SHUTDOWN STRONG FUME SCENT IMMEDIATELY AFTER TURNING ON APU BLEED. SHUT OFF BLEED WITHIN 5 SECONDS OF NOTICING THE SMELL. COMPLETED LEVEL A DECONTAMINATION OF THE ENVIRONMENTAL CONTROL SYSTEM (ECS) PER WORKCARD 2100-2007. (LP 7458663)