As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTED SMOKE IN COCKPIT ON TAXI. MECHANIC INSPECTED WIRING COMPONENTS IN AIRCRAFT INTERIOR AND FOUND NO DAMAGED COMPONENTS OR WIRING. ALL SYSTEMS GROUND CHECKED GOOD THRU MULTIPLE POWER CYCLES EXCEPT AN ABANDONED AVIONICS COOLING FAN. MECHANIC CAPPED AND STOWED THE COOLING FAN POWER AND GROUND WIRES.