Circuit/System Description
WARNING: This page is about a different car, the 2008 Cadillac XLR. However, it is still accessible from the selected car via links, so may be relevant.
The left keyless entry antenna is located in the right hand B-pillar area and is used as a short range low frequency (LF) transmitter. As a vehicle with locked doors is approached with a key fob and the exterior door handle switch is pressed, the keyless entry antenna transmitter broadcasts a challenge to the key fob in an approximately 1 meter range. If the response from the key fob via radio frequency (RF) is valid, the locked door will be passively unlocked/unlatched and allow the door to be opened.