As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE SITTING AT GATE NOTICED SMOKE/SMELL IN AFT CABIN. GROUND PERSONNEL STATED SMOKE CAME FROM EQUIP COOLING FAN EXHAUST. MTC INSPECTED ALL AREAS WHERE EQUIP COOL AIR DRAWN WITH NO ABNORMALITIES. RAN ENGINES AND ALL ASSOCIATED SYSTEMS, NO TROUBLE FOUND. PULLED BOTH NORMAL AND ALTERNATE FANS TO INSPECT. NO TROUBLE FOUND.