What was found
DFW - FLT 0746 - DURING DESCENT INTO DFW WITH LANDING GEAR UP, NOSE LANDING GEAR RED LIGHT ILLUMINATED WITH NO OTHER ABNORMAL INDICATIONS. LANDING GEAR EXTENDED NORMALLY AND AIRCRAFT LANDED DFW WITHOUT INCIDENT. DURING TROUBLESHOOTING, COOLED NLG LOCK SENSOR USING CIRCUIT COOLER AND NOSE GEAR RED LIGHT ILLUMINATED. REPLACED NLG LOCK SENSOR. SYSTEM GROUND CHECKED, NORMAL OPERATION. (X)