Hello Craig,
Is there any sign of water ingress around/above the fuse box on the drivers side?or around the bcm on the passenger's side? Do the windows work or the central locking switch on the dash? Does the gear position show correctly on the instrument cluster?
Also, joking about petrol , has it got enough in it , as I have had one of my own vehicles log a fault for the immobiliser before, which wouldn't clear, but it turned out that it was low on fuel, but I doubt this is your problem as you say that there is no spark or fuel.Have you checked the inertia switch?Does the vehicle lock/unlock using the fob?
regards, Andrew