As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FIRST TAKEOFF ATTEMPT, RECEIVED TAKEOFF WARNING HORN. BRAKES SET 1.4 EPR ALL ENGINES, FLAPS 15 DEGREES, APU OFF, STAB TRIM IN GREEN ARC, AND SPEED BRAKE STOWED. ON RUNWAY VERIFIED ALL POSSIBLE INPUTS. MOVED STAB TRIM REV AND FWD. THE HORN CONTINUED TO SOUND UNTIL REDUCED THRUST. MAX SPEED REACHED WAS 30 KTS. TAXIED CLEAR OF RUNWAY. RETESTED TAKEOFF WARNING HORN SYSTEM. THIS TIME IT FUNCTIONED PROPERLY.