How do you replace an alternator in a 2005 Mazda 6?

To replace the alternator in a 2005 Mazda 6, first disconnect the negative battery cable to ensure safety. Remove the serpentine belt by loosening the tensioner, then disconnect the electrical connectors from the alternator. Unbolt the alternator from its mounting bracket and carefully remove it. Install the new alternator by reversing the steps: secure it in place, reconnect the electrical connectors, and reattach the serpentine belt before reconnecting the battery.