My battery is fully charged and when I go to start the car it makes a fast clicking sound.
It sounds like you may have a faulty battery connection resulting in insufficient power getting from the battery to the starter. This may cause the rapid clicking sound you are hearing. I woulds suggest checking all connections to the battery and making sure it is properly grounded. You may also want to have the battery load tested to be sure it does in fact still have a full charge. If you need further help with this, please reach out to us here at YourMechanic as we are always here to help.
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