Circuit/System Description

WARNING: This page is about a different car, the 2008 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.

The console active antenna is located in the center console and is used as a short range low frequency (LF) antenna. The keyless entry console active antenna is only used when a keyless entry transmitter battery is low or there is a interruption with the frequency transmission of the passive antennas located in the console and headliner. When a valid transmitter is placed into the fob pocket, the brake pedal is depressed, and the ignition button is pressed, the console active antenna broadcasts a challenge to the transmitter. This causes a low frequency coupling to occur between the transmitter and the console active antenna. If the response from the transmitter is a valid response, and all of the security requirements are met, the vehicle's engine will start, or be allowed to go into accessory mode.