As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED"WHEN APU IS STARTED WHILE THE ENGINES WAS RUNNING LOUD CRACKLING AND SMELL OF SMOKE AND BURNT AND ELECTRICAL ALSO HAPPENED DURING ENGINE SHUT DOWN". CONTRACT MX INSPECTED COCKPIT AREA FOR LOOSE OR DAMAGED ELECTRICAL ITEMS AND FOUND ELECTRICAL INNER CONNECTION BAR UNDER COCKPIT FLOORING TO HAVE A LOOSE TERMINAL. TIGHTENED IAW EMB145 AMM 24-65-01. OPS CHECKED GOOD. A/C WAS APPROVED FOR SERVICE.