click wheel doesnt work w/ auto stereo anymore

i have a 60g iPod. i installed a Pioneer stereo w/ a plug in adapter. it use to work fine. if my iPod had a full charge i could use my click wheel to scan through my artist or have my passenger watch a movie and hear it through my trucks stereo. does not work that way anymore. now my iPod only says "ok to disconnect". i have to use the stereos access buttons. i have 1200 artists on my iPod. i could drive across the country before i'de get to the end. anyone have an idea how to get my click wheel to work like it did.