I have a 99 chrysler cirrus. The temperature blend control was not working properly. Felt like the cable or linkage was jammed. I gained access to the linkage and it appeared the gears that connect the cable to the door were out of line. While attempting to correct this problem, the gear to the blend door broke off. How do I replace this?

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.

The most likely problem is either the blend door actuator or a broken blend door itself.
Both are only accessible by complete removal of the instrument panel(dash).
The blend door actuator can be tested with a Chrysler factory scan tool hooked up to the DLC(data link connector). If blend door actuator is working when tested with the factory scan tool, then blend door itself is at fault.
The only other way to test the blend door actuator is to test for 12v at connector, but you would have to remove the instrument panel in order to gain access to the actuator

Sounds like you need to replace the air temperature control blend door and blend door actuator. This job requires the entire dash be removed in most cases.

Stuck doors or broken connection

According to the book, I'm showing a mode actuator and a blend door actuator next to it. Some models use cables and some use small electric motors to move the doors.
Are you sure you are working on the right door ?

If the heater is working correctly, and the air temp does not stay the same coming from different outlets, the problem could be a blend door under the dash. The blend doors direct air thru the heater core and out the vents.

Check the blend door cable for proper attachment to the control panel and to the blend door. Try opening the door manually to see the you can get hot air out. If not, the door may be broken inside the heater box. If yes, correct/adjust the cable attachment for proper operation.

REMOVAL & INSTALLATION
1990-97 Passat Models
Install the cable ends marked with a white or blue band to the control head assembly. The cables must be attached to the control head before connection to the system air flaps.

1. Remove the climate control head from the center dash assembly to access the control head cable ends.
2. Remove the lower dash panels as necessary to access the cable lever arms.
3. Attach the airflow distribution cable (cable 2) to the airflow distribution knob's lower control lever.

This cable can be identified as follows:
Operates the mode/central air flap Cable has a black sleeve and is 25.0 inches (634 mm) long Cable is marked with a white band

1. Press the cable's sleeve against the control head stop and install the retaining clip.
2. Attach the temperature control/air blend cable (cable 3) to the air temperature knob's control lever.

This cable can be identified as follows:

Operates the temperature control/air blend cable air flap Cable has a blue sleeve and is 21.0 inches (535 mm) long Cable is marked with a white band

1. Press the cable's sleeve against the control head stop and install the retaining clip.
2. Attach the airflow distribution cable (cable 1) to the airflow distribution knob's upper control lever.

This cable can be identified as follows:


Operates the footwell/defroster air flap Cable has a black sleeve and is 37.5 inches (954 mm) long Cable is marked with a blue band

1. Install the cable such that the blue band is over the retaining clip mount and install the retaining clip directly over the blue band.
2. Install the climate control head.
3. Set the air flow distribution knob to defrost.
4. Connect the longest airflow cable (cable 1) to the footwell/defroster flap lever on the heater's air box.
5. Press and hold the flap's lever toward the retaining clamp perch and install the cable retaining clip.
6. Set the airflow distribution knob to the Vent position.
7. Connect the short airflow cable (cable 2) to the central/mode flap's lever.
8. Pull and hold the mode flap's lever away from the retaining clamp perch and install the cable retaining clip. Check the operation of both air flaps making sure they can be heard contacting their stops.
9. Set the temperature control knob to full cold.
10. Connect the blue-sleeved cable (cable 3) to the air blend/temperature flap's lever.
11. Pull and hold the mode flap's lever away from the retaining clamp perch and install the cable retaining clip. Check the operation of the air blend/temperature flap making sure it can be heard contacting the stops.

Fig. Side view of the control head and cable location. 1. Footwell/defrost flap cable-2. Air distribution cable-3. Temperature control flap cable

Fig. Temperature flap cable location and adjustment

Possible bad thermostat, or your blend door is not working properly.

Your temperature control cable, knob or blend door actuator is (are) defective. Lower the glove by pulling the side tabs in and allowing it to hang down. Now you will have access to determine if your temperature control is defective or your blend door is not opening properly.

I'm reading the instructions at autozone.com, and I don't see anything about removing the dash. You do have to pull out the trim around the control unit and unscrew the unit to get to the back of it, but I don't see why you can't get to all the cables and doors by sticking your head under the dash. If I were you, I would do it myself. This would be about a 1 hr job for me. Maybe a little longer if I was new at it...let me know if you want me to copy the instructions and send them on.