As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FREON AIR CONDITIONER WAS WORKING ON PREVIOUS FLIGHT. WHILE INVESTIGATING A ELETRICAL BURNING ODOR ON GROUND, DISCOVERED THE FREON AIR CONDITIONER TO BE INOPERATIVE AND LIKELY THE CAUSE OF THE ODOR. OPERATED SYS MOTOR FAILED TO RUN. FOUND OPEN FUSE LIMITER IN J-BOX AND EVIDENCE THAT MOTOR FAILED. R & R A/C MOTOR. SERVICED REFRIDGERANT. LEAK AND OP CHECKED GOOD. WORK DONE IAW MM 21-52-00.