For 1990-2009 cars

The power antenna extends to the full UP position when the radio is turned ON and the ignition switch is in the RUN or ACCESSORY position. The antenna will also extend if the radio is turned ON during retained accessory power. The power antenna retracts to the full down position when the radio is turned OFF. The antenna will also retracts when the ignition switch is turned OFF or after retained accessory power turns OFF.