astravan not starting

[F3Rob]

Hi all, hopefully there is someone here who can help. i have had a search but nothing found as of yet.

I have recently changed the Alternator and drive belt of my 1.3 CDTI astravan and not it wont start,

what have i tried???
i have checked all fuses
new battery

i am now stuck as to what it might be.

i think it possibly is a relay? can anyone please help?

 

[Burnerman]

Is the engine actually cranking over, or is everything dead?
If the engine does crank, I'd guess the immobiliser needs rebooting somehow.....is the dash lamp flashing when you try?
John