How do you know if its the starter?
The first indication your starter may be going bad is at the moment you try to start your car. If you turn the key and simply hear a clicking sound, or nothing at all, then it may be the starter. If they light up properly, then the problem is not with the battery and is likely the starter.
How do I know if my starter has power?
Will starter click if battery dead?
A rapid clicking noise when trying to start your car could mean there's something wrong within the electrical system. Perhaps your battery's dead, or your alternator, which charges the battery, isn't working correctly. So instead, it rapidly turns on and off and produces a clicking noise!
Related Question How do you tell if its your starter or your battery?
How do you tell if a car battery has a dead cell?
If the battery cannot reach higher than 10.5 volts when being charged, then the battery has a dead cell. If the battery is fully charged (according to the battery charger) but the voltage is 12.5 or less, the battery is sulfated. Sulfation is the natural byproduct when the battery discharged.