Cadillac Repair Questions? Ask a Mechanic for Answers ASAP
have you checked the fuses for those items?
Here is your owners manual, the fuse start on page 6-106, check them.
The radio fuse is the rdo fuse #42 in the underhood fuse block at the left side of engine compartment.
According to Chilton, " The body control module (BCM) supplies B+ to the rearview camera when the transmission is placed into reverse"
I see one simple test for that backup camera: