As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BURNING PLASTIC ODOR DURING LATER PART OF DECENT DETECTED IN COCKPIT ONLY. ODOR DISAPATED WHEN LEFT PACK WAS SWITCHED OFF. ACCOMPLISHED TROUBLESHOT THE CABIN AIT QUALITY 26L00021001. INSPECTED APU BAY FOUND NO OIL LEAKS FOUND DEFORMED APU INLET SEAL WITH EVIDENCE OF DEICE FLUID LEAK PAST SEAL INTO INLET REPLACED SEAL RAN APU BLEED NO ODOR DETECTED REF AMM 49-16-00.