There may be an issue with your amp in the trunk. Make sure your amp is still there (no one stole it, lol), and that you are getting power to the amp. Radio sound and chime are wired in series with the amp.
My 2000 Impala does not have the large orange wire that splits into two, and I don't see any corrosion. However, I have no door chime or speaker sounds. Would there be another location for the corrosion?