if your ignition key is part of the imobiliser system.similar to astra 2000 model.
the key is a transponder(it means it has a code chip inside)and if its not letting u turn the key,its not reading it,you need to have your key reprogramed
dependant on your key.if it has remote locking n unlocking buttons on it
john bulmer (bulmer44@hotmail.co.uk), June 2007