Strange clicking noise inside interior when truck is off

[Tahoe_SSV]

Hello all, So when I turn vehicle off and am sitting in it, there is a strange "click" every 30 seconds or so inside cabin .any ideas what this might be?

 

[Doubeleive]

Hello all, So when I turn vehicle off and am sitting in it, there is a strange "click" every 30 seconds or so inside cabin .any ideas what this might be?

I would guess a blend door actuator is faulty and is trying to move to the commanded state when off.
after 10 minutes (maybe less depending) the system goes into full sleep mode and you should not hear it anymore until you wake it up by turning the key.
if you scan it with a bi-directional scanner like a tech2 you may find some blend door errors after it fails to work a few times it makes a historical code in the bcm, this type of error does not cause a check engine light.

 

[OR VietVet]

What @Doubeleive said.

 

[Tahoe_SSV]

I did change the MODE door accuator under driver's dash a few days or so before I noticed the click every 15 30 seconds. maybe I didnt properly install? I am not sure. It still does it.