As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - FLT 1536 - THE LEFT GEAR UNSAFE LIGHT ILLUMINATED DURING THE GEAR UPLATCH CHECK AFTER DEPARTING IAH. CYCLING THE GEAR AND REPEATING THE UPLATCH CHECK GAVE NO CHANGE. THE AIRCRAFT WAS RETURNED TO IAH WHERE IT LANDED WITHOUT INCIDENT. THE LANDING GEAR PROXIMITY SWITCH CONTROL BOX WAS REMOVED AND REPLACED. A CHECK OF THE LT MLG UPLATCH SENSOR SHOWED PROPER CLEARANCE. SEVERAL GEAR RETRACTIONS AND EXTENSIONS WERE PERFORMED AND ALL GEAR INDICATIONS WERE NORMAL. (X)