Dead diesel

[bodgit]

I,ve not used my car a 2lt tdci cmax since 20 nov as I was away. I tried to start it this morning and its dead almost like a flat battery but the battery is holding 12.8v. It seems like the engine can barely turn over.
I did not have this problem last winter throughout those long icy months we had. Onboard temp reads -6c.
A failure message comes up on the comp but too quick to read before it goes out and there seems to be a noise from the fuse/relay passenger area and when you take the key out the speed and rev needles bounce a bit and a crackling noise comes from behind the dash.
Is this just a case of wait till it warms up or frozen diesel.
Any ideas welcome.