Without a little more specifics this is hard to answer. When you say it doesn't work, is it not responding to voice commands? Does the screen not work? Does the touch screen not work? What is the MY of your vehicle? It may still be under warranty because the nav systems are fairly new in the Odyssey but at this point it's hard to determine.Most likely the issue will need to be dealt with by the dealer. I hate to say that but there aren't many places that would have the technical understanding to fix such a device. The dealer won't either but will most likely replace the entire nav unit and replace it.As far as if you choose to update the nav system the dealership has a virtual lock on this. You can also get the updates through Honda's website. I believe they run about $275 but I haven't priced them lately.