With a single zone heating-A/C system, you'll find a single blend door actuator, while the dual zone system includes actuators for both the driver and passenger sides. For the driver side, place the blend door actuator on the driver side of the HVAC air distribution housing, connect the wire harness connector and lock it by pushing on the red tab. Join the actuator to the air distribution housing by aligning the splines with the blend door linkage, if needed and keep it in place with two screws tightened to 1.2 Nm (10 in. lbs.). Stick the knee blocker in the driver seat and then connect back the negative end of the battery cable. Finally, restart the car and reset the A/C-heater control. With reference to dual zone, place the blend door actuator in the passenger section, clip the wire harness on and turn the red tab. Mount the actuator onto the bracket on the air distribution housing by aligning the splines, then screw it in and tighten all four screws to 1.2 Nm (10 in. lbs.). When the vehicle has a silencer, set it in place under the passenger side of the instrument panel, hook the negative battery cable back up and adjust the A/C-heater control.