As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LAS - ABORTED TAKEOFF - FLT 0399 - ON TAKEOFF AT LAS EN ROUTE FOR DFW THE TAKEOFF CONFIGURATION WARNING HORN SOUNDED COUNTINUOUSLY, RETURNED TO GATE. MAINTENANCE REMOVED EXCESSIVE GREASE AT SWITCHED S132 AND S546, REPLACED LEADING EDGE FLAP CIRCUIT BREAKER AS A PRECAUTION. TAKEOFF WARNING SYSTEM TEST WAS GOOD PER T/C A1B31009.