Where is the body control module located?

Hello, there looks to be two modules in this vehicle considered to be Body Control modules, what kind of issue are you having? There is a rear integration module and a dash integration module. Each control different sections of the vehicle. I'll post the diagrams for both as well as the GM serial data diagram.
Diagrams 1 and 2(lower half) are the Dash BCM, diagrams 3 and 4 are the Rear BCM, and diagrams 5 and 6 is the GM Serial Data network which shows both BCMs in the lower diagram. If there happens to be a module failure issue, you're dealing with the Splice connectors for the network are a good place where you can disconnect each module one by one if needed.

https://www.2carpros.com/articles/how-to-check-a-car-fuse