Why is the ford ranger making a clicking noise under dash?

A Ford Ranger clicking noise under the dash could be the blend door actuator failing. The blend door actuator is a small electric motor that features sensors connected to Your truck's climate control system. As You adjust the temperature up and down, or the intensity of the airflow, the signals go through the actuator. An actuator can become faulty if the plastic gear set turns out to be fragile and it breaks. Another common sign that the actuator is going bad is if the heater in Your truck is blowing cold or the AC is blowing hot.