For 1990-2009 cars

The power antenna extends to the full up position when the radio is ON and the ignition switch is in the RUN position or the ACCESSORY position. The antenna also extends if the radio is ON during retained accessory power (if equipped). The power antenna retracts to the full down position when the radio is OFF. The antenna also retracts when the ignition switch is OFF or after retained accessory power turns OFF (if equipped).