As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AFTER LEVELING OFF AT 6000 FEET A WARNING HORN - NO OTHER INDICATIONS. SLOWED THE AIRCRAFT DROPPED THE GEAR - GOT 3 GREEN LIGHTS. BROUGHT THE GEAR UP THE HORN CAME BACK ON. NO INDICATIONS AGAIN. RETURNED TO JFK HORNED CONTINUED IN UP OR OFF. REMOVED AND REPLACED THE PROXIMITY SENSOR ELECTRONIC UNIT AS PER AMM 32-09-10 AND MCM CARD 08C00032003.