Circuit/System Description
WARNING: This page is about a different car, the 2015 Cadillac SRX. However, it is still accessible from the selected car via links, so may be relevant.
When the transmission is placed into REVERSE, a 12 V signal is sent to the B87 Rearview Camera indicating that camera operation is requested. Ignition voltage and ground are supplied to the rearview camera. The rearview camera sends video information to the K74 Human Interface Control Module through a video signal + and a video signal - circuit. A grounded shielding also wraps the video signal circuits to reduce electronic interference which may degrade the video signal and cause a distorted or otherwise degraded image.