Rear Heated Oxygen Sensor

Disconnect the negative battery terminal.
Disconnect the heated oxygen sensor connector (A).

Courtesy of KIA MOTORS AMERICA, INC.
Remove the heated oxygen sensor (A) by using the SST (09392-1Y100)
Tightening torque :

39.2 - 49.1 N.m (4.0 - 5.0 kgf.m, 28.9 - 36.2 lb.ft)

Courtesy of KIA MOTORS AMERICA, INC.