As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - FLT 310 - SMOKE NOTED IN CABIN. INSPECTED APU AREA FOR LEAKS, NONE FOUND. POWERED UP AIRCRAFT, FOUND RIGHT AIR CONDITIONED PACK SWITCH ON IN AUTO WITH AN EXTERNAL AIR CONDITION UNIT PLUGGED INTO AIRCRAFT. NO SMOKE NOTED AFTER DISCONNECTING EXTERNAL AIR CONDITION UNIT FROM AIRCRAFT. (M)