Interesting, but a few caveats.
A generic device (and an el cheapo Bluetooth OBD interface coupled to a copy of "Torque" on Android is a good place to start) will read some/most of the sensors and usually the fault codes too. If you're very lucky, the fault reset function may work on your car.
Trouble is that, while the interface is standard, manufacturers do like to make much of the data format proprietary, so to get at everything you will need that hideously expensive manufacturer's service computer....
Biting the hand that feeds IT
