p38 with fault code 27 "alarm system"

hi, out there anyone clever enough to know a way of relearning immobilizer code without going to dealer or having the use of T4 ?
battery went flat (so whats new eh!)
and is now just turning over but wont fire not getting diesel
going by info on various forums its the fuel immobilizer not being recognized by the remote key fob
any help would be muchly appreciated
jim

it'll need t4 or rovacom or similar, try posting in the rr section thers a few guys with it, quite spread out in uk so one will be able to help