If you're trying to start your car and you hear a clicking noise, there could be numerous reasons for it. You'll have to note down the pattern of that clicking to determine its exact cause, though. For example, a barely audible and light yet singular click is likely coming from the starter relay. Meanwhile, a louder yet singular click may come from a starter solenoid. Noises from either the starter relay or solenoid can be tough to diagnose. It's possible that the entire starter is malfunctioning. Or, if it's not getting enough current from the battery. On the other hand, rapid and repeated clicking means that your starter is working fine. But, it's not getting enough current (most likely because of a bad or weak battery) to start the car.