As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHEN GEAR WAS EXTENDED ON APPROACH TO IAH THREE GREEN GEAR DOWN LIGHTS AND THREE RED GEAR UNSAFE LIGHTS WERE ILLUMINATED. THE GEAR WAS RECYCLED DURING A GO-AROUND AND ALL INDICATIONS WERE NORMAL. THE AIRCRAFT LANDED WITHOUT INCIDENT. MAINTENANCE REMOVED AND REPLACED THE M983 AND M986 LOGIC CARDS. INDICATION AND OPERATIONAL CHECKS WERE GOOD.