Audio Systems: Audiophile stereo, audio logic, digital mode

Question
Hi. I have a 2005 f150 with the 6 dics mp3 player Audiophile stereo and the bass stopped working. No matter where you set the bass it does not change the sound but the bars move as if it is going to change the sound. any ideas what might of happened and is it a easy fix?

Answer
I'll answer this question with a question since I am no expert on consumer or car audio. Logic generally applies to most equipment but I first need to know exactly what is an f150 6 CD changer. If you can download the PDF manual send it to me and I will look it over and give you my opinion. In my experience when equalization doesn't work it generally means that there is a direct digital mode that bypasses all eq or a dedicated output that is direct digital.