Heater flap control wasn't working. I've seen many videos on how to fix this and most people seem to buy a new unit rather than repairing the servo motor itself. It is very easy to repair:

1: Remove glove box (approx 8 screws and its out)
2: With ignition on move each of your controls to see which servo motor is not responding - easy to spot each one moving
3: Disconnect electrical plug on the suspect servo motor
4: Remove the 3 screws holding the servo motor in place and disconnect the actuator arm
5: Open up the servo motor by pushing the tabs out with a fine blade
6: Check the attached photo - you can remove the little motor and two cogs easily
7: Clean them up and use some silicone lubricant
8: Put it back together and test with either a 12v bench supply or plug it back in the car

One word of caution, make sure you either mark or take a photo of the original position of the rotation arm before disassembly....


Servo motor actuator arm

Opened up showing two cogs and potentiometer

Close up view showing motor fully and cogs.