Front Door Latch Lock Jammed Shut Whilst Turning Handle

[E46Touring]

Hi All

My front door lock is a night latch type, very similar to the one pictured below



Yesterday I turned the handle to open the door from the inside, and when it got to the 4 or 5 'o'clock position where it normally turns the latch to open the door, it got very stiff & almost got stuck (possibly because of the cold because my heating had been off all day), and when I got it past that bit and turned it all the way down it made a kind of snapping sound, the door latch didn't release and now the handle is stuck below the latch release point and won't go back up. So I can't open the front door & am using the back door at the moment. The only screws are on the side of the box so I can't reach them with the door closed.

I'm wondering if because of the nearly freezing temps had the mechanism inside had frozen & snapped? Is there any other option apart from removing the door?

Thanks in advance.

[Doctor DG]

It sounds to me like there has been a breakage on the latch retractor inside the lockscase or that the screws on the backplate ( to the inside of the lock) have come loose.Disassemble and see. Or replace like for like is easy enough and not expensive. You can keep your cylinder if you replace to save getting keys cut.

kind regards