What was found
DFW - FLT 0619 - AFTER TAKEOFF WHEN GEAR HANDLE WAS RAISED, ALL GREEN GEAR INDICATING LIGHTS WENT OUT. NOSE GEAR RED INDICATING LIGHT REMAINED ILLUMINATED. GEAR DOOR OPEN LIGHT WAS OUT. LOWERING THE GEAR HANDLE RESULTED IN NORMAL INDICATION FOR GEAR DOWN. RETURNED TO DFW AND LANDED OVERWEIGHT WITHOUT INCIDENT. REPLACED NOSE GEAR UP/DOWNLOCK SENSOR. PERFORMED REQUIRED INSTALLATION AND OPERATION CHECKS INCLUDING NOSE GEAR SWING. SYSTEM GROUND CHECKED, NORMAL OPERATION. (X)