Module, Hands Free Liftgate: Operation

WARNING: This page is about a different car, the 2020 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

As someone approaches the hands free liftgate activation area, the hands free liftgate capacitive sensors wake up the hands free entry module from a sleep state. When a valid kick is detected, the module sends a toggle signal to wake the Body Control Module (BCM). The BCM then contacts the Radio Frequency Hub (RF-Hub) module to ping for valid key fobs. If a valid key fob is found the RF-Hub then signals the BCM that it is okay to open the liftgate. The BCM commands the Power Liftgate Module (PLGM) to open.

A valid signal is defined as the customer making a forward kick motion under the vehicle. The process for a successful kick entails entering zone one, entering zone two, exiting zone two and exiting zone one of the sensor's range within the set time.

Activation is restricted if the vehicle's key fob is not within range of the rear passive entry antenna.

The customer performs a valid "kick" under liftgate.
The hands free zone sensors detect the valid "kick" request.
The hands free module sends a message to the BCM over the Local Interface Network (LIN) bus.
The BCM sends a message to the PLGM. If the Power Liftgate (PLG) is not locked or is not closed, the PLG opens.
If the PLG is closed and locked, the PLGM sends a message to the BCM which gates the message to the RF-Hub requesting a key fob search
.
The RF-Hub searches for a key fob in the designated area and if a valid key fob is found, the RF-Hub sends a message to the BCM which gates the message to the PLGM.
If a key fob was found in the designated area, the PLGM then open the liftgate.