k12 boot lock

[jools jool]

my 2004 micra had the dreaded boot lock failure back in 2005 it got a recall and was working fine but its started to do it again opened twice as i was driving down motorway so got in contact with nissan but they says its been fixed for free once before so they wont do it again am a bit skint so is there a way ov stripping old boot mech and cleaning ive seen some things on ebay which state you can do this and they send you a pdf file to follow doe's anyone no if it can be done or is it a trip to a breakers yard for 2nd hand one thanks in advance