The blend door actuators are reversible, 12-volt direct
current (DC), servo motors. Models with the single
zone heating-A/C system have a single blend-air door,
which is controlled by a single blend door actuator.
Models with the dual zone system have two blend-air
doors, which are controlled by two blend door actua-
tors.

The blend door actuator (1) for the single zone heat-
ing-A/C system is located near the center of the HVAC
housing (2), close to the dash panel.

For the dual zone heating-A/C system, the same
blend door actuator used for the single zone system
becomes the driver side blend door actuator, which is
mechanically connected to only the driver side blend-
air door. A second separate blend door actuator (3)
located on the top of the HVAC housing is mechani-
cally connected to the passenger side blend-air door.

All actuators (1) are interchangeable with each other.
Each actuator is contained within an identical black
molded plastic housing with an integral wire connector
receptacle (2). Each actuator also has an identical
output shaft with splines (3) that connect it to its
respective door linkage and three integral mounting
tabs (4) that allow the actuator to be secured to the
HVAC housing. The blend door actuators do not
require mechanical indexing to the blend-air doors, as
they are electronically calibrated by the A/C-heater
control.

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OPERATION

The blend door actuators are connected to the A/C-heater control through the vehicle electrical system by a dedi-
cated two-wire lead and connector of the HVAC wire harness. The blend door actuator(s) can move the blend-air
door(s) in two directions. When the A/C-heater control pulls the voltage on one side of the motor connection high
and the other connection low, the blend-air door will move in one direction. When the A/C-heater control reverses
the polarity of the voltage to the motor, the blend-air door moves in the opposite direction.

When the A/C-heater control makes the voltage to both connections high or both connections low, the blend-air door
stops and will not move. The A/C-heater control uses a pulse-count positioning system to monitor the operation and
relative position of the blend door actuator(s) and the blend-air door(s). The A/C-heater control learns the blend-air
door stop positions during the calibration procedure and will store a diagnostic trouble code (DTC) for any problems
it detects in the blend door actuator circuits.

The blend door actuators are diagnosed using a DRBIII

scan tool (Refer to 24 - HEATING & AIR CONDITIONING

- DIAGNOSIS AND TESTING and to 24 - HVAC Electrical Diagnostics for more information).

The blend door actuators cannot be adjusted or repaired and, if faulty or damaged, they must be replaced.

REMOVAL

WARNING: On vehicles equipped with airbags, disable the airbag system before attempting any steering
wheel, steering column, or instrument panel component diagnosis or service. Disconnect and isolate the
battery negative (ground) cable, then wait two minutes for the airbag system capacitor to discharge before
performing further diagnosis or service. This is the only sure way to disable the airbag system. Failure to
take the proper precautions could result in accidental airbag deployment and possible personal injury or
death.

NOTE: The single zone heating-A/C system is equipped with a single blend door actuator. The dual zone
system has two blend door actuators, one for the driver side blend-air door and one for the passenger side
blend-air door.

SINGLE ZONE/DUAL ZONE DRIVER SIDE

1. Disconnect and isolate the negative battery cable.

2. Remove the instrument panel from the vehicle

(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL ASSEMBLY - REMOVAL).

3. Remove the two screws (1) that secure the blend

door actuator (2) to the back of the HVAC housing
(3).

4. Remove the blend door actuator from the HVAC

housing and disconnect the HVAC wire harness
connector (4) from the actuator.

5. Remove the blend door actuator from the vehicle.

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DUAL ZONE PASSENGER SIDE

1. Disconnect and isolate the negative battery cable.

2. Remove the instrument panel from the vehicle

(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL ASSEMBLY - REMOVAL).

3. Remove the blend door lever (1) from the blend

door actuator output shaft (2) and the blend door
linkage (3).

4. Remove the two screws (1) that secure the blend

door actuator and bracket assembly (2) to the top
of the HVAC housing (3).

5. Remove the blend door actuator and bracket

assembly from the HVAC housing and disconnect
the HVAC wire harness connector (4) from the
actuator.

6. Remove the blend door actuator and bracket

assembly from the vehicle.

INSTALLATION

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