Does this mirror plug into the factory wiring harness?

Yes — it uses the OEM electrical connector. No rewiring needed if your vehicle came equipped with powered mirrors from the factory.

What if my car didn't come with heated mirrors originally?

The heating element is built in, but your vehicle needs the factory heated mirror wiring already present to activate the function. If your Optima lacks heated mirror circuitry, the power adjustment will still work.

Are mounting brackets included?

Mirror assembly comes ready to bolt on using factory attachment points — hardware for final installation is not included. Standard fasteners work with OEM mounting holes.