Boot lock?

I took my 307 to car wash and some how water has got in somewhere to the electrics ,the wipers came on and the lights ,indicaters or nothing electrical would work ,I've rebooted the car but the boot won't open ,I had just replaced the boot lock so somehow the water has got to it again , would anyone have any idea where abouts the water would be getting in ,any suggestions would be much appreciated .Thanks Rodney