Smartphone Compatible Automobile Diagnostic Tool

[mhunt3]

I haven't seen anything like this, but it would be very cool. The idea is a dongle that connects to your car and transmits information to your phone via BT. The tool could give diagnostic codes, fuel efficiency, allow you to reset the check engine light, etc. If anyone has come across something like this for a smart phone, let me know. Here is something similar that Garmin offers with select GPS devices:

http://www.garmin.com/garmin/cms/us/services/ecoRoute