Tick-Tock from upper C pillar?

[HiImBrian]

There is a tick tock sound coming from my drivers side upper C pillar. It only happens when I transfer the rear AC from the roof vents to the floor vents... AC door actuator?

 

[43]

the ticking in mine came from the 3rd row where the acutal A/C was housed when my actuator went, not from the pillar... but the ticking definitly sounds like it. Also mine would only tick when the temp was too low or too hot, didnt matter where the air went... interesting!