Had the same thing on a 53, blame the French. Japanese car, BUT the book lock made by Renault. Have a look on Ebay for something called K12 boot repair. (I think.) Basically water is getting into the mechanism. For 99p the guy on ebay sends you an email with pictures and instructions on how to fix. As long as you can handle a screwdriver, and bend into the corners it's pretty simple repair.
Antony, December 2011
anyone southport area repair micro boot lock, have switc h and bits carlos said buy, but rubbish at repairs , please, please
george, September 2011
Try getting someone to bang on the hatch near the lock mechanism as you operate the remote. That may get it open. If not, then a visit to your dealer for a new lock may be the answer.