As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - CREW REPORTED GEAR DOWN INDICATIONS WERE RED. SECOND TIME GEAR INDICATION LIGHTS WERE RED BUT THEN TURNED GREEN. TOWER VERIFIED GEAR WAS IN THE DOWN POSITION. FLIGHT LANDED DFW WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED PROXIMITY SENSOR ELECTRONICS UNIT. SYSTEM GROUND CHECK NORMAL OPERATION.