As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FIRE ALARM & SMOKE DETECTOR IS GOING OFF NOTE NO HEAT. SMOKE DETECTOR 10 MIN LATER SMELLED SMOKE & TURNED OFF PACK & FIRE ALARM WENT OFF. IAW NR 4701755 APU HAS INTERNAL OIL LEAK-REPLACED, PERFORMED AMM 21-00-01-002-001 REMOVAL OF OIL CONTAMINATION. CONDITIONED AIR HAS NO SMELL OF OIL CONTAMINATION. OK TO CONTINUE.