I know this is an old thread but i stumbled across it a couple of days ago whilst trying to find an answer. My Focus (MK2) boot handle was not working since i bought the car whitch i didn't really mind as i just used the key. But it started unlocking on its own unless the car was locked. This got really annoying really quick. Iv searched around any there docent seem to be a definitive answer. Mainly just people saying that it was down to water ingress. so i thought id have a little mess with it and see what i could do. I peeled back the rubber of the boot handle to find i full to the brim with water and a white power/residue After i seen how bad it was i took it apart from the inside and gave it a good clean. Wiped everything and gave anything Easily detachable a good soak in the sink. It was a hot day so i drove around without the Rubber on the handle to air it out. And then Blasted the handle and cover in WD40 (to evaporate any left vapour). Since putting it back together its been fine. The boot handle still does not work (in need of a new switch). But it sees to have fixed the unlocking problem. Hope this helps.