This is the one preoccupying me today. My service light is on in the van. It costs me $41 for a level-1 diagnostic (that means: plugging the scanner into the
OBD-II plug, reading out the alarm, and resetting the flag). For $59 plus shipping, I can get an
OBD2/USB converter, and my laptop can then use
pyOBD to do that for free from then on. I see this as a no-brainer.
OK, but imagine this: the
OBDuino project can put an Arduino board onto that port. And Arduino can support WiFi. So let's build that as a unit; when you get your car home, it handshakes with your home WiFi network and provides its interface as an HTTP service. Now you can run diagnostics - and other OBD-enabled things like mileage trends and so on - from the comfort of your desk. Not to mention detect when your car comes home (sky's the limit on that).
Total cost for a kit: probably around $50-75. Sale price? $150? Sounds worth it to me; I'd probably buy that right now.
There's some
commercial product in Germany based kinda on this (with an in-car LED readout, which could be an add-on option), although it seems to be a kit, not a consumer item. I want a consumer item. The same guy has a list of
OBD interface standards by model (the
plug is standard, but there are five interface "standards", typical of the auto industry). Here's
another (lacking current hosting). This would also be an interesting searchable database, actually: a data project. And
another, for a commercially available tool.
That's my link dump for this idea so far. If you use this, tell me - I'll be your first customer. Next post will be a breakdown and research to-do.