What was found
FLT 4911 - DURING TAKEOFF IN CLIMB, THE PILOT CALLED FOR GEAR UP. THE F/O TRIED SEVERAL TIMES TO MOVE THE GEAR HANDLE UP, BUT WAS UNABLE. THE PILOT DIRECTED THE F/O TO USE THE DOWNLOCK RELEASE BUTTON AND TRY AGAIN, WHICH WAS STILL UNSUCCESSFUL. DFW MAINTENANCE HAD THE PILOT REPEAT THE PROCEDURE, ALSO UNSUCCESSFUL. THE AIRCRAFT RETURNED TO DFW AND HAD AN UNEVENTFUL LANDING. DFW MAINTENANCE REMOVED AND REPLACED THE RIGHT PROXIMITY SWITCH HARNESS. OPERATIONAL CHECKS WERE GOOD. AIRCRAFT RETURNED TO SERVICE. (M)