As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CABIN BECAME HAZY WITH SMOKE & BURNING SMELL WITH APU RUNNING & BLEED ON. THIS HAPPENED ABOUT 45 MIN AFTER LANDING AT THE GATE WITH ENG OFF RIGHT BEFORE BOARDING PAXS. ACCOMPLISHED JOB CARD 26L00021001. NO DEFECTS NOTED. NO ODORS AT THIS TIME. ACFT OK FOR SERVICE.