deano im pretty sure it will be the problem i posted
as usually before the piece breaks it still makes a poor contact (hence the waggling and occasionally it works)
this is until it breaks totally then stops alltogether ........
poor design much like the vauxhall two button keys which also do exactly the same thing ...
renault cards are very problematic and i personally would also get a spare card aswsell if you only have the one as it will eventually break alltogether trust me lol ..
anyway to the op hope you get it sorted
and if all else fails try this http://www.youtube.com/watch?v=4vIvZ4uuB0M