[Bank 1/Sensor 2]

Turn the ignition switch OFF and disconnect the battery negative (-) terminal.
Lift the vehicle.
Remove the rear under cover.

Fig 1: Identifying Rear Under Cover
Courtesy of KIA MOTORS AMERICA, INC.
Disconnect the heated oxygen sensor connector (B).
Remove the heated oxygen sensor (A).

Fig 2: Identifying Heated Oxygen Sensor
Courtesy of KIA MOTORS AMERICA, INC.