What was found
SMF - ABORTED TAKEOFF - FLT 0259 - DURING TAKEOFF ROLL AT SMF THE TAKEOFF WARNING HORN SOUNDED, TAKEOFF WAS ABORTED. RESET THE FLAPS, TRIM, AND SPEEDBRAKES; REATTEMPTED TAKEOFF BUT HORN SOUNDED AGAIN. MAINTENANCE CLEANED THROTTLE SWITCHES AT OVERHEAD IN E/E BAY; COMPLIED WITH TAKEOFF WARNING SYSTEM TEST T/C A1B31009, TAKEOFF WARNING SYSTEM CHECKED GOOD.