As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR CONDITIONING COMPRESSOR SHUT ITSELF OFF WHILE ON THE GROUND WITH GROUND POWER UNIT, IMMEDIATELY CREATED A SMOKY ODOR INSIDE THE CABIN. BLACK SMOKE WAS VISIBLE COMING OUT OF THE AFT EQUIP COMPARTMENT, TURNED OFF THE POWER & OPENED THE AFT BAGGAGE DOOR. R & R A/C COMPRESSOR PALLET ASSEMBLY IAW MM 21-52-00. SERVICED A/C SYSTEM IAW MM 12-19-02. OPS CHECKED GOOD.