Remove the spare wheel and you can get at the mechanism up under the rear of the hood -- odds are that either the end nuts have become loose so the wire won't move the left hand release far enough, or that one of the release mechanisms which are held in by two nuts has come loose and the wire pull isn't doing anything.
I hope it is the former as getting the nuts on the latter is not easy as access for a spanner is very difficult. - Don't ask how I know!!!!!!!!
Cheers!
