If your car has an Immobiliser problem, it may be caused by a number of things. The most common cause is a faulty Immobiliser unit, which can be caused by a number of things, including a faulty transponder key, a faulty Immobiliser control module, or a faulty Immobiliser antenna. Other causes of Immobiliser problems can include a dead battery, a blown fuse, or a disconnected Immobiliser antenna.