MY 2002/52 GTV had a dead battery. I replaced it and the car started and ran for about 1 mile then died. Now it turns over on the battery but will not fire and there is a key logo illuminated on the dash. Sounds as if its immobilised itself. Car is stuck on the roadside so I need urgent advice. Can anyone help. I only have one key, bright red with the alfa logo and the immobiliser is a remote push button type which seems to be operating ok but obviosly not sure. It locks and unlocks the car.