whats more LIKELY the case, is that Scion said: "these are the iPod cable specs, make it to these specs" (which at the time, supported firewire based charging). Scion doesnt come up with the specs, apple does. i'm sure scion used a vendor, and then labeled it with their own part #, cuz last i checked, Scion is a car company, not an electronics company.
so since then, the 2nd gen ipod touch and iphone 3G have been released, which do NOT support firewire based charging.
http://support.apple.com/kb/HT1476
which is why you're facing the issue you face now. i would look into the solution deggie provided.