Cassette adapter in 1990 lexus ls400?

I bought a cassette adapter to use with my iphone so I can listen to music in my car. I press "tape" but it just says "tape" on the deck and goes back to playing the radio, not even playing my music. Is there a solution to this?

The radio can see that there's no film in this tape because its a fake tape not a tape and believes the tape broke before it gets stuck it turns off the tape there's no solution to this, there's a sensor inside the radio, to listen to your music install this device to your radio

http://www.oemautosound.com/p-720-fm-universal-aux-input-modulator-hard-wired-usb.aspx