As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: APU WENT OFFLINE, BUT A VERY STRONG ELECTRICAL BURNING SMELL WAS IN AIRCRAFT CABIN AND FLIGHT DECK. AFTER APU RESTART. ACCOMPLISHED WORK CARD 08L00021001 FOR SMOKE ODOR FUMES, FOUND OIL COOLER FAULTY. REMOVE AND REPLACED OIL COOLER (AALA202406046456), PER AMM 49-91-41. ALSO REMOVE AND REPLACED LOW OIL PRESSURE SWITCH (AALA202406043169), PER AMM 49-94-22. ALL OPERTIONAL AND LEAKED CHECK GOOD.