As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FLIGHT 4317 FROM IND TO RDU APU PRODUCED SMOKE SMELL AND SMOKE TOLIET MESSAGE ON DECENT WHEN PACKS RUN OFF OF APU. SMELL WENT AWAY WHEN SWITCHED BACK TO 10TH STAGE BLEEDS. MAINTENANCE DEFERRED THE APU. COMPLETED APU OPS CHECKS AND BLEED AIR TRANSFER SQUENCE FROM ENGINE TO APUI IAW AMM 49-10-00. NO DEFECTS NOTED HAS NORMAL CRJ200 ODOR, THIS CLEARS MEL 49-10-11 AUTH 71578.