As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) HEATER SYS WAS PLUGGED IN AND A ODOR OF BURNING PLASTIC/WIRE WAS SMELLED AND THE 7.5A BREAKER POPPED. UNIT UNPLUGGED UPON RETURN THE NEXT DAY TO BASE THE TRANSMISSION PAD, PLUG WAS FOUND TO BE IN A MELTED STATE. THE ACFT WAS PLACARDED AS TANIS HEATER, UNUSABLE.