03 range rover torque clutch converter p0741

bought used 2003 range rover with 65k miles,, drove it for a week and now i get service engine soon.. my mechanic looked at it and told me that it brings up code for Torque Clutch Converter - P0741. Car was driving Ok before and now when it shifts, makes a little noise. I think that it is a Converter went dead. Anyone knows who can fix it or if I just should take it to a dealer and let him look at it. Also, how much this fix can run me parts and labor?
any info is appriciated.
thanks in advance