As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TAKEOFF CONFIGURATION WARNING HORN SOUNDS WHEN THRUST LEVERS ADVANCED TO TAKEOFF POWER. CHECKED CONDITION AND RESISTANCE CHECK NR 1 AND NR 4 EXT. PROXIMITY SWITCH OK. REPLACED FLAP/SLAT POSITION SWITCH UNIT MODULE. OPERATIONAL CHECK OK PER TAKEOFF WARNING. AIRRAFT RETURNED TO SERVICE. (M)