Error 41 is Print head needs to be replaced, on this model it is not a big job, Heads can be purchased from Brother dealers, ring brother to locate if you wish to repair this machine rather than replace it.
Head sells for about $80 for the part from a brother dealer 1-800-284-4329 and it will need a new set of inks too, not really worth it just replace with new machine with ink and a warranty.
Very common issue, brother extended warranty for this fault for two years but yours would be past it by now, the s/n tells of build date, the first two digits of the LAST NINE of the serial number indicate build date, so a K6J702822 ending serial no. means it was built K6 = Nov 06.
I beleive that this is a result a lot of the time by the use of refills and remanufactured ink cartridges being used.
There is heaps of info on net regarding "error 41".