Diagram of blend door actuator and of all connections to actuator

Replacing the air blend door actuator (commonly known as the air blender) on a 2005 Lincoln Aviator is a moderately challenging task that requires some mechanical know-how and the right tools. The air blend door actuator is responsible for controlling the temperature of the air that comes out of the HVAC system by adjusting the position of the blend door. If you're confident in your abilities, follow these general steps to replace the actuator:
Note: Before starting any work, ensure the vehicle is turned off and the battery is disconnected to avoid electrical hazards.
Tools and Materials Needed:

• Screwdrivers (Phillips and flat-head)
• Socket and ratchet set
• Trim panel removal tool (optional)
• New air blend door actuator
• Shop manual or repair guide for your specific vehicle (for reference)

Step-by-Step Guide:

1. Locate the Actuator: The air blend door actuator is usually located behind the dashboard, in the HVAC housing. Access to it may require removing some interior panels and components, so consult your vehicle's repair guide for specific instructions on gaining access to the actuator.
2. Disconnect the Battery: As a safety precaution, disconnect the negative terminal of the battery to avoid electrical mishaps while working on the vehicle.
3. Remove Interior Panels: Depending on the location of the actuator, you may need to remove portions of the dashboard or other interior panels to access it. Use a trim panel removal tool or a flat-head screwdriver wrapped in cloth to avoid damaging the panels.
4. Disconnect Wiring Harness: Once you have access to the actuator, locate the wiring harness connected to it. Gently disconnect the wiring harness by pressing the release tab and pulling it away from the actuator.
5. Remove Actuator Mounting Screws: The actuator is usually secured to the HVAC housing with screws. Use a socket and ratchet or a screwdriver to remove these screws and detach the actuator from the housing.
6. Install the New Actuator: Position the new air blend door actuator in place and secure it with the mounting screws. Make sure it is properly aligned with the blend door and HVAC housing.
7. Reconnect Wiring Harness: Attach the wiring harness back to the new actuator, ensuring a secure connection.
8. Test the Actuator: Reconnect the negative battery terminal and turn on the vehicle. Test the new actuator by adjusting the temperature controls and checking if the blend door moves accordingly.
9. Reassemble Interior Panels: Once the actuator is functioning correctly, reassemble any interior panels or components you removed earlier.
10. Test the HVAC System: After reassembly, test the entire HVAC system to ensure everything is working correctly. Check for any unusual noises or issues with temperature control.

Always follow safety precautions and consult your vehicle's repair manual for specific instructions and diagrams related to your Lincoln Aviator's model year. If you are unsure or uncomfortable performing this task, it is best to seek assistance from a professional mechanic.

1. Locate the blend door actuator. The actuator is located behind the dashboard, usually on the passenger side. It is a small, rectangular motor with a wiring harness and a linkage arm.
2. Disconnect the battery. Before beginning any work on the electrical system, disconnect the battery to avoid any electrical shorts or other accidents.
3. Remove the dashboard panel. In order to access the blend door actuator, the dashboard panel may need to be removed. Consult the vehicle's repair manual for specific instructions on how to remove the panel.
4. Remove the old blend door actuator. Disconnect the wiring harness and the linkage arm from the old blend door actuator. Remove any mounting screws or bolts that secure the actuator to the dashboard.
5. Install the new blend door actuator. Install the new blend door actuator in the same location as the old actuator. Secure the actuator with any mounting screws or bolts. Connect the wiring harness and the linkage arm to the new actuator.

Temperature Blend Door Actuators The dual-zone EATC system uses 2 temperature blend door actuators to control 2 separate temperature blend doors. The temperature blend doors independently vary the LH side and RH side temperature settings, as desired. The temperature blend door actuators each contain a reversible electric motor and a potentiometer. The potentiometer circuit consists of a 5-volt reference signal connected to one end of a variable resistor, and a signal ground connected to the other. A signal return circuit is connected to a contact wiper, which is driven along the variable resistor by the actuator shaft. The signal returned to the EATC module from the contact wiper indicates the position of the temperature blend door. The EATC module drives the actuator motor in whichever direction is necessary to make the actuator contact wiper voltage agree with the expected EATC module contact wiper voltage value.

Right side or left ? Electronic Automatic Temperature Control or manual ? Temperature or mode door ?
Temperature Blend Door Actuator - LH Removal and Installation
NOTE: It is not required to install the new LH temperature blend door linkage parts included in the LH temperature blend door actuator service part kit if only the temperature blend door actuator requires replacement and the linkage parts are not broken or binding.
LH temperature blend door actuator and linkage

1. Remove the 2 lower steering column opening cover bolts.

1. Detach the lower steering column opening cover.

1. Disconnect the in-vehicle temperature sensor aspirator hose and electrical connector.

1. Position the instrument panel wire harness away from the LH temperature blend door actuator.

1. Remove the 3 LH temperature blend door actuator screws.

1. Disconnect the LH temperature blend door actuator electrical connector.

1. Remove the LH temperature blend door actuator.

1. Manually operate, and inspect the LH temperature blend door linkage for incorrect placement, binding or damage.

Temperature Blend Door Actuator - RH, Dual-Zone EATC Removal and Installation
NOTE: It is not required to install the new RH temperature blend door linkage parts included in the RH temperature blend door actuator service part kit if only the temperature blend door actuator requires replacement and the linkage parts are not broken or binding.
RH temperature blend door actuator and linkage

1. Disconnect the glove compartment damper from the glove compartment.

1. Remove the glove compartment.

1. Remove the RH lower instrument panel insulator.

1. Remove the RH lower floor console trim panel.

1. Remove the 3 RH temperature blend door actuator screws.

1. Disconnect the RH temperature blend door actuator electrical connector.

1. Remove the RH temperature blend door actuator.

1. Manually operate, and inspect the RH temperature blend door linkage for incorrect placement, binding or damage.
2. Mode Door Actuator - Defrost/Panel/Floor Door
3. Removal and Installation
   NOTE: The defrost/panel/floor mode door actuator can be accessed from below the driver side of the instrument panel.
   NOTE: It is not required to install the new defrost/panel/floor mode door linkage parts included in the defrost/panel/floor mode door actuator service part kit if only the mode door actuator requires replacement and the linkage parts are not broken or binding.
   Mode door actuator and linkage
   1. Remove the 3 defrost/panel/floor mode door actuator screws.
   1. Disconnect the defrost/panel/floor mode door actuator electrical connector.
   1. Remove the defrost/panel/floor mode door actuator.
   1. Manually operate, and inspect the defrost/panel/floor mode door linkage for incorrect placement or damage.
   Mode door actuator linkage only
   
   1. Remove the mode door linkage.
      1. Depress the tab and remove the panel door lever.
      1. Remove the floor/defrost door intermediate lever screw and floor/defrost door intermediate lever.
      1. Pull straight outward to remove the floor/defrost door lever.
   Mode door actuator and linkage
   
   1. NOTE: When installing the mode door actuator, make sure that the panel door lever and floor/defrost intermediate lever are correctly aligned with the mode door actuator cam.
      To install, reverse the removal procedure.

Have to get a wiring diagram at a local repair shop

or buy the factory book from Helm.Com

it is controlled by an electronic actuator. look up blend door actuator on google with your year make and modle and it will show a diagram and location, also a part number if you would like to replace.

i have replaced actuator motor on blend door and new switch on 2000 S-10 and blend door still does not work . Please help .

The most likely cause is a failed blend door actuator; however I recommend a little troubleshooting. First, can you hear a clicking sound behind the dash when you turn the setting to hot? If yes, it is certainly the actuator stripping its gears. If not, check to make sure the heater hoses are both hot as they connect to the heater core at the firewall (in the engine compartment). If one or both of the hoses do not get hot, there is a blockage caused either by an air bubble or a stuck water control valve in the heater hose. If the hoses are both hot, the indication is again the blend door actuator.

Below are instructions for replacing the actuator. Look at the diagrams carefully--the big arrows point to the front of the truck and the actuator is on the side of the heater box above the outlet duct that runs to the driver's side of the floor. Also, the actuator is expensive, so I recommend you make sure it's bad and shop around a bit to get a good price. To check out the actuator, first see if you can turn the blend door by hand. If you can't turn it, maybe it's jammed. Also, reconnect the actuator after removing it and see what it does when you turn the heater to hot.

Removal & Installation

1. Remove the floor air outlet duct extension (1) from the floor duct (2).
   

   

Fig. Remove the floor air outlet duct extension (1) from the floor duct (2)

Disconnect the electrical connection at the blend door actuator (#10 in pic below).

Fig. Blend door actuator and related components

Remove the blend door actuator mounting screws from the HVAC module.

Remove the blend door actuator as an assembly with the actuator cam.

Fig. Remove the blend door actuator mounting screws from the HVAC module

To install:

1. Install the blend door actuator as an assembly with the actuator cam.
   1. Line up the heater/defroster valve lever with the blend door actuator cam slot.
   2. Line up the A/C valve lever with the blend door actuator cam
   
   
2. Install the blend door actuator mounting screw to the HVAC module.
   1. Tighten the blend door actuator mounting screw to 14 inch lbs. (1.6 Nm).
   
   
3. Connect the electrical connection at the blend door actuator (10).
4. Install the floor air outlet duct extension (1) to the floor air duct (2).

Picture of actuator:

there is a blend door actuator for the laredo and if is bad the air wont come out here is a pic of what it looks like and how to get to it


The single zone heater-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.

1. Disconnect and isolate the negative battery cable.
   
2. Remove the glove box from the instrument panel.
3. Remove the three screws that secure the blend door actuator to the passenger side of the HVAC air distribution housing .
4. Remove the blend door actuator from the air distribution housing and disconnect the HVAC wire harness connector from the actuator.
5. Remove the blend door actuator from the vehicle

to instal

1. Position the blend door actuator into the vehicle.
2. Install the blend door actuator onto the passenger side of the HVAC air distribution housing . If necessary, rotate the actuator slightly to align the splines on the actuator output shaft with those on the blend door cam .
3. Install the screws that secure the blend door actuator to the passenger side of the air distribution housing . Tighten the screws to 17 inch lbs. (2 Nm).
4. Connect the HVAC wire harness connector to the blend door actuator.
5. Install the glove box into the instrument panel.
6. Reconnect the negative battery cable.

I would look at the air blend doors first, it sound like they are not working or your control in the dash is not working send a signal to them. they work by changing the air from hot to cold or in between.

Avalanche, Sierra And Silverado

1. Remove the floor air outlet duct extension (1) from the floor duct (2). Remove the floor air outlet duct extension (1) from the floor duct (2)
2. Disconnect the electrical connection at the blend door actuator (10). Blend door actuator and related components
3. Remove the blend door actuator mounting screws from the HVAC module.
4. Remove the blend door actuator as an assembly with the actuator cam. Remove the blend door actuator mounting screws from the HVAC module

To install:

1. Install the blend door actuator as an assembly with the actuator cam.
   1. Line up the heater/defroster valve lever with the blend door actuator cam slot.
   2. Line up the A/C valve lever with the blend door actuator cam
2. Install the blend door actuator mounting screw to the HVAC module.
   1. Tighten the blend door actuator mounting screw to 14 inch lbs. (1.6 Nm).
3. Connect the electrical connection at the blend door actuator (10). Blend door actuator and related components
4. Install the floor air outlet duct extension (1) to the floor air duct (2).

C/K Series

1. Disconnect the electrical connector to the mode actuator that is located on the left side of the air distribution case.
2. Remove the screws.
3. Remove the adjuster links from the control lever.
4. Remove the mode actuator.
5. Adjust the mode actuator by completing the following steps:
   1. Connect the electrical connector to the actuator.
   2. Turn the ignition switch to the RUN position. Allow the self-positioning of the actuator.
   3. Turn the ignition switch to the OFF position.
   4. Remove the actuator from the electrical connection. Blend door actuator-C/K Series

To install:

1. Install the mode actuator.
2. Install the screws.
3. Install the adjuster links to the control lever.
4. Connect the electrical connector.
5. Test the circuit operation