What do you know about OBD-II?

[Mcninch]

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..!

[EHaskins]

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.

[Branden Ghena]

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 ;)

[Matt Howard]

OBD is good for Diagnosing problems, but that's about it. Without high $$ hardware, you cant do much else with it.

[Prelude_SH]

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.

[DonRotolo]

It would probably make a pretty awesome project... for after build season of course ;)
Just avoid causing damage to that very expen$ive engine control unit...
OBD is good for Diagnosing problems, but that's about it. Without high $$ hardware, you cant do much else with it.
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.

[Matt Howard]

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.

[Mcninch]

Thanks guys! I appreciate your very informative replies.

[Tobot]

I've been using an Ultragauge (http://www.ultra-gauge.com/ultragauge/index.htm) 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 (http://ecomodder.com/forum/em-fuel-log.php?vehicleid=3586).

Some of the newer cars report over 70 sensor outputs through OBD-II. It's a pretty rich data stream.

[Matt Howard]

A Vacuum gauge is all you need to hypermile. That tool is simply a detuned codepuller.

[drakesword]

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