As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BIL - FLT 5011 - PILOT REPORTED A 'FLASH' IN THE INSTRUMENT PANEL AND SMELLED WIRE INSULATION BURNED. BRASS SCREW BACKED OUT OF THE ENGINE TACHOMETER MOUNT AND CONTACTED THE HOT PORTION OF THE INDIRECT LIGHTING BULB. SECURED SCREW IN TACHOMETER MOUNT, LIGHTING SYSTEM OPS CHECKED GOOD. AIRCRAFT RETURNED TO SERVICE.