iPod Classic 160gb not recognized by car usb

My car's USB port no longer recognizes my iPod Classic 160gb. The dashboard display just says "READING" forever. The iPod works fine on its own. I've tried changing USB cables with no change in reception. The car does recognize my iPhone when connected to the same port with the same cable, so it looks like the problem is with the iPod. Any suggestions for how to address the issue?

Try plugging it into a PC to see if it can be read. If it can't be read on a PC (or a Mac, whichever you have) there may be a problem with the output port. If it's still under warranty, take it to Apple and have them check it out.

My Mac not only reads it but iTunes can add songs to it which then play normally when I listen with headphones.

This is really irritating me. Not only have the songs that I converted from cassette and vinyl disappeared from iTunes, but so have my own original compositions. So Apple feels this burning, all-consuming need to protect me from pirating myself???