Aux input cable not working?

I've tried a couple different cables from my phone the the aux connection. I've also turned the volume up and both the stereo and phone, but nothing at all. What am I missing here? Anything? Does this cable run directly into the back of the stereo? Just wondering if I have to remove the stereo, which I was trying to avoid. Could it be a faulty cable? Maybe a fuse?
Thanks for any suggestions.



