Active Antenna
WARNING: This page is about a different car, the 2010 Cadillac SRX. However, it is still accessible from the selected car via links, so may be relevant.
The active antenna system uses two integral antennas applied as appliques to the rear glass. Each antenna is part of the rear window and looks similar to the defogger grid. One antenna receives AM signals while the other antenna receives FM signals. Any damage to the antenna requires replacing the glass.
The radio antenna module is enabled when the radio is turned on. The radio provides battery voltage to the antenna module using the center conductor of the antenna coaxial cable. This DC voltage does not affect the incoming radio signal. When a 12 V signal is seen by the module on the center conductor of the antenna coax, both AM and FM signals are amplified.