Another door lock problem - but this one's intermittent???

[QuattroSheikh]

Hey Guys,

Since the start of the beautiful heat upon us, the front passenger side door won't unlock from the outside - it opens from the inside with no problem? If I lock it then it works normally again. It also seems to work OK if away from direct sunlight for a period of time.

Any thoughts would be gratefully appreciated or if anyone else has experienced this??

Thanks,