Keyless Entry Control Module
WARNING: This page is about a different car, the 2019 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.
The Keyless Entry Control Module uses low frequency antennas in three different locations on the vehicle to determine the location of the transmitter. Multiple antenna are used to ensure complete coverage of the vehicle interior and rear compartment. The Keyless Entry Control Module monitors the ignition mode switch. When the ignition mode is changed, the Keyless Entry Control Module will command, or "ping", the low frequency antenna.