Heater is not working?

Hello,

It sounds like you might have an issue with the blend door actuator. As it is stuck at one position and making the clicking noise.
The blend door actuator is what controls the flow from hot to cold air.
It is located under the dash on the passenger side (see diagram below)

Here is an article you might find helpful:

https://www.2carpros.com/articles/replace-blend-door-motor

I have also attached the diagrams for the blend door actuator/motor.

Please let me know of any questions.

Thank you.