Theory Of Operation
WARNING: This page is about a different car, the 2016 Dodge Durango. However, it is still accessible from the selected car via links, so may be relevant.
Four relays are used to provide voltage to the Trailer Tow connector. The trailer tow relays are used to switch fused battery voltage directly to the Trailer Tow connector when requested. The trailer tow relays are activated through a ground path provided by the Body Control Module (BCM).