Comments On Trouble Symptom
WARNING: This page is about a different car, the 2014 Mitsubishi Outlander. However, it is still accessible from the selected car via links, so may be relevant.
If the air conditioning outlet temperature cannot be adjusted, the air mixing damper control motor or the heater controller assembly (A/C-ECU) may be faulty.
NOTE:
It cannot be adjusted while the engine coolant temperature is low.