locked xj40 boot (trunk)
 

I think the link between the cylider and latch has boken or come adrift, will not unlock by key or via remote, how can I open it without damage?

Welcome to the forum Graham, for tech questions please post into the section for your car, ie XJ40 section. (moving this over there now).

However, which colour key are you trying with, the green one will not open the boot at least mine won't.

Have you tried the button in the glove box?

Either will mine. And the green key is the only one I have.