whats this called?

[lowdown112]

94c1500 what is this: https://youtu.be/JL-Gu95_tY0

Its supposed to be buzzing but its clicking real hard? Its round with a green and red/white wire connector goin to it mounted to the firewall behind the glovebox and behind the black box

 

[skylark]

It it one of the actuators for the hvac. The noise happens when something is broken, usually in the air box.

 

[someotherguy]

http://www.chevytalk.org/fusionbb/showtopic.php?tid/170970

Richard