Check your dock connector, make sure that there are no bend, broken or corroded pins. Clean it out with some compressed air. If that is okay and your iPod still does not turn on, it is time to disassemble it and replace the battery first. It is the cheapest way to make sure that your iPod has no other problems. Here is how you do it iPod Classic Battery Replacement and you can get the battery from here iPod Classic (Thin) Replacement Battery Hope this helps, good luck.