2011 C4s
Removed the little plastic split bars on the front-sides the car, where the two side radiators are. Was able to manipulate a vacuum into the recess to vacuum out leaves. Noticed what seems to be two smaller radiators underneath the two side radiators. (??) Are they additional cooling veins for something? So what does my center radiator do - engine cooling? What do the side radiators cool? What about the additional radiator/cooling vein under the side radiators?

 

1st radiator is for the AC. The one behind is engine cooling. Center is engine cooling.

 

This. The left and right side have a radiator sandwich, AC in front with engine coolant in back. If you have a radiator in center of the front bumper it's coolant only (aka the third radiator).