51 plate 307 LX, I have just bought, in excellent condition MOT'd until OCT. Cranks but will not start. Immobiliser will not reset. OBD terminal is dead. Central locking and all lights etc will not work. Key code missing. Passenger airbag has deployed. Key fob replaced, new battery, 2 new switches, immobiliser in place. Tried to reset using key lock hold down technique many times. On ignition dash lights come on as do headlights. Is ECU fried? Was working fine until owner disconnected battery. Should I just 'phone scrap car collection. At my wits end now. Thanks for reading.