As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON ENTERING COCKPIT ELECTRICAL ODOR WAS PRESENT AND AC BUSS 2 LIGHT IS ON AND TR2 POPPED. FO REPORTED CLOUDY SMOKEY AREA IN BACK OF AVIONICS BAY. FOUND EXTERNAL POWER OUTPUT ON JETWAY LOW. RESET TR2 BREAKER, USED APU GENERATOR. ALL VOLTAGE CHECKS GOOD. ODOR IS COMING FROM DOOR ENTRY CABIN LIGHT BALLAST. REPLACED BALLAST, PN 8178 SN ON 031412, SN OFF 013990. ALL CHECKS GOOD.