As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WITH AIRCRAFT ON GROUND SERVICE POWER TURNED BATT PWR SW ON AND POWERED AIRCRAFT WITH GROUND POWER. WITHIN 5 MINUTES STRONG ELECTRICAL BURNING SMELL IN COCKPIT. DEPOWERED AIRCRAFT. T/S AND FOUND PILOTS FMA AT FAULT/ FMA LOOSE IN HOUSING/ FORWARD PANEL. CAPTAINS PANEL PULLED BACK FOR MAINT REF AMM 22-17. REPLACED CAPTAINS FMA PER AMM 22-17. PERFORMED RTS PER AMM -22-10 SYSTEM CKS GOOD.