Reading up on some gadget news today, I read that all cars manufactured since 2000 have OBD-II installed beneath the dashboard, which enables it to communicate with gadgets such as the ‘AutoBot’ (tracks your car) and CarTrip (stores your car data on an iPhone). I was wondering who has actually experience with using the OBD-II with these or similar gadgets? Sounds interesting…!
Acctually, since 1996 they’ve had OBD-II.
It is what your mechanic uses when they connect a diagnostic scanner. Essentially, anything your car’s computer knows is available through it.
If you are interested you should talk to your auto shop instructor.
I haven’t actually played around with it myself, but NerdKits has a tutorial on interfacing electronics with the OBD-II in your car. http://www.nerdkits.com/videos/obdii/
It would probably make a pretty awesome project… for after build season of course 
OBD is good for Diagnosing problems, but that’s about it. Without high $$ hardware, you cant do much else with it.
OBDII is for diagnosing CEL, SRS, etc. codes.
Easy to pull, at least on my car. the dashboard flashes all the lights in a certain series depending on the problem.
Just avoid causing damage to that very expen$ive engine control unit…
I disagree.
Yes, you can read out the On-Board Diagnostic (OBD) fault codes, which can help in diagnosing the problem. But there is a wealth of vehicle operational data available on that connector, such as fuel economy, vehicle speed, and more.
Inexpensive (<$100) testers are readily available.
The “high $$ hardware” are manufacturer systems, which work on every system in the car (like A/C, seats, locks, etc.), not just the emissions-relevant ones covered by the OBD laws.
As for the original post: There is a LOT of info on the web about OBD II, since it’s a publicly-documented system. The OBD connector is under the dash, but the ‘computer’ behind it can be located anywhere.
We’re thinking on two different wavelengths here. By diagnosis I was encompassing everything you stated.
The the expensive tools I am thinking of, are for performance programming. Fuel maps, engine management, timing advancement, 02 Delete, disabling emissions control devices, things of that nature.
Thanks guys! I appreciate your very informative replies.
I’ve been using an Ultragauge for about 6 months. I have been really pleased with it. It helped me push my average fuel economy in my car over 50 mpg.
Some of the newer cars report over 70 sensor outputs through OBD-II. It’s a pretty rich data stream.
A Vacuum gauge is all you need to hypermile. That tool is simply a detuned codepuller.
OBD-II comunicates via can right?
Hook a black jag into it and read the data from the serial end of the jag.
Use the jag later to build a robot or
use the jag to use your car as the robot
Win-Win-Win