Theory Of Operation
WARNING: This page is about a different car, the 2021 Chrysler 300. However, it is still accessible from the selected car via links, so may be relevant.
The Radio Frequency (RF) Hub is connected to a fused B(+) circuit and has a path to ground at all times. These connections allow it to remain functional regardless of the ignition switch status. Any input to the RF Hub that controls a vehicle system function that does not require that the ignition switch status be ON such as depressing a button on an Remote Keyless Entry (RKE) or Frequency Operated Button with Integrated Key (FOBIK) transmitter, prompts the RF Hub to wake up and transmit on the CAN data bus. The RF Hub uses On-Board Diagnostics (OBD) to monitor all hard wired inputs, outputs, functions and conditions for the circuits it controls.