I think its usually the cam gears that break/strip but it could be the splines, I dunno. If its the cam gears I think you replace the entire housing (#17). I think the AC recallibrates the actuator about 5 minutes after the power is turned off. The passenger side actuator is #7 in the last figure below. These are the service manual words (and figures):
The blend door actuators (1) are reversible, 12 volt direct current (DC), servo motors. Both dual zone heating-A/C systems use two blend-air doors, which are controlled by two blend door actuators.
The driver side blend door actuator is located on the driver side end of the HVAC air distribution housing and is mechanically connected to the driver side blend-air door. The passenger side blend door actuator is located on the passenger side of the air distribution housing and is mechanically connected to the passenger side blend-air door.
The blend door actuators are interchangeable with each other, as well as with the actuators for the mode-air doors and the recirculation-air door. Each actuator is contained within an identical black molded plastic housing with an integral wire connector receptacle (2). Each actuator 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 air distribution housing. The blend door actuators require mechanical indexing to the blend-air door cams and are electronically calibrated by the A/C-heater control.
The blend door actuators are connected to the A/C-heater control through the vehicle electrical system by a dedicated 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(s) 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 actuators and the blend-air doors. The A/C-heater control learns the blend-air doors 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 actuator(s) is diagnosed using a scan tool (Refer to 28 - DTC-Based Diagnostics/HVAC - Diagnosis and Testing) .
The blend door actuator(s) cannot be adjusted or repaired and must be replaced if inoperative or damaged.
RIGHT SIDE REMOVAL
1.Disconnect and isolate the negative battery cable.
2.Remove the right side instrument panel silencer.
3.On LHD models, remove the glove box and glove box closeout (Refer to 23 - Body/Instrument Panel/GLOVE BOX, Instrument Panel - Removal) .
4.Remove the right side floor distribution duct from the HVAC air distribution housing (4) (Refer to 24 - Heating and Air Conditioning/Distribution/DUCT, Floor Distribution - Removal) .
5.Remove the two screws (1) that secure the blend door actuator (3) to the right side of the air distribution housing.
6.Remove the blend door actuator from the air distribution housing.
7.Disconnect the wire harness connector (2) from the blend door actuator and remove the actuator from the vehicle.
RIGHT SIDE INSTALL
1.Position the blend door actuator (1) into the vehicle.
2.Install the blend door actuator onto the right side of the HVAC air distribution housing (4). If necessary, rotate the actuator slightly to align the splines on the actuator output shaft (2) with those on the blend door drive gear (3).
3.Install the two screws (1) that secure the blend door actuator (3) to the right side of the HVAC air distribution housing (4). Tighten the screws to 2 N·m (17 in. lbs.).
4.Connect the wire harness connector (2) to the blend door actuator.
5.Install the right side floor distribution duct (Refer to 24 - Heating and Air Conditioning/Distribution/DUCT, Floor Distribution - Installation) .
6.On LHD models, install the glove box closeout and the glove box (Refer to 23 - Body/Instrument Panel/GLOVE BOX, Instrument Panel - Installation) .
7.Install the right side instrument panel silencer.
8.Reconnect the negative battery cable.
9.Initiate the Actuator Calibration function using a scan tool (Refer to 28 - DTC-Based Diagnostics/HVAC - Standard Procedure) .
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