autoxray

January 12, 2004 10:11 PM

Hack your car. AutoXRAY scans internal vehicle computers and gives detailed diagnostics and real-time graphing output.
posted by stbalbach (11 comments total)

See also the Crash Data Recorder interface, which is available in a growing number of cars, to meet NTSB standards. In actuality, all cars have small computers, and all cars with airbags have Event Data Recorder functionality -- but the manufacturers have not devised or provided the interface (in one case, a police request for an analysis of an EDR with a non-approved interface was a failure, even though GM sent one of their top EDR techs).

Though there are privacy concerns, with new state laws reaching the books, courtroom demand is increasing and it's a federal crime for an authorized service provider to disable the EDR (at the very least, it could theoretically interfere with airbag deployment).

Anyway, the EDR functionality isn't the same thing, exactly, as the performance computer functionality; they aren't on the same chip, for one thing. This just takes shade tree mechanic to a whole new level. (And it's forcing a national shake-out in the auto mechanics field. I know two people including my brother who'd rather do something else, like drive over the road, than become an engine "computer tech".)
posted by dhartung at 11:46 PM on January 12, 2004

I know that my families 2002 Impala LS has the Onstar system, so that you can call for free and ask if there is any problems with your car. The problem is that they can only get basic error diagnostic codes. They couldnt tell me the PSI of my tires, even though the car has pressure sensors. Slowly but surely, car computers are going to become somewhat user friendly, either by hacking the interface or an in house attempt.

What I want to see is a software app with a cheap car plug. The computer can easily do all of the work (as im sure many mefites know much more than me about ECM's and Chip systems)
posted by Keyser Soze at 12:46 AM on January 13, 2004

(Disclaimer: In a former life, I've worked on the software side of an OBD II scanner that competes with this one.)

Aside from manipulating the fuel-air ratio, what kind of "hacking" could one do with one of these? It's pretty much a read-only tool, though you can toggle the self tests with it. All OBD II provides is a spec for querying the sensors.
posted by swell at 1:06 AM on January 13, 2004

swell, what's the competitor? I was thinking with the PC interface it should be possible to hook up a laptop with an internet connection and stream data real-time to a website. Why? It would be cool to watch remotely a car being driven. That's what I meant by "hack", cool but useless.
posted by stbalbach at 8:55 AM on January 13, 2004

This is really cool. I try to do as much with my car as possible, but I usually fall short if it requires technical knowledge of the computer data. Do I have an example? Yes I do.

My speedometer on my 95 Jeep GC stopped functioning properly (they stopped using cables to measure speed a long time ago apparently). Since it was just a mess of wires, I could do nothing but take it in. The mechanics first hooked up their computer and said they couldn't get a read off the "speed sensor" and that could be whats causing the problem. After offering no alternatives to solve it, they spliced in a new $35.00 sensor for a cool $91 an hour. After messing around with it some more they realized it wasn't the sensor. The actual sensor was fine (but they were really hesitant to say it didn't need to be replaced for some reason), and that it was the actual dashboard that needed to be replaced. The dashboard costing $350 by itself and needing 2 weeks so they could set the odometer at the factory. All said and done it cost $770, that's with the fit I threw and them crediting me a couple hours of labor.

So if I get this program it theoretically could save me the diagnostic since apparently its all the mechanics use themselves anyway. Really could pay for itself very soon.
posted by geoff. at 9:15 AM on January 13, 2004

Oh not to be a knock on mechanics, they do know what they're doing, its the billing system that's screwed up.
posted by geoff. at 9:26 AM on January 13, 2004

An even better "hack" would be to put a small computer in your car that grabbed the EDR or performance data and logged it along with other info. For example, you could leave a voice message like "leaving for client XYZ" and "arrived home." Or, your could interface your GPS into it. Or the weather. Then, all this could be combined and dumped out to a home system by wifi when you got home. This way, you could completely analyze your business mileage, or see if a performance issue was related to wet weather or a steep incline, etc. There are millions of cars driven every day, yet we know more about the performance of our hard drives than we do our cars. Sounds like we need a sourceforge project started!
posted by rman666 at 11:43 AM on January 13, 2004

This is just one of many OBD II code pullers. Fun, but not a whole lot you can do with them short of reading and resetting codes. The real fun would be getting a client your vehicle manufacturer's proprietary diagnostic and control interface and having a wide open door to your ECU... but they tend to keep a close grip on those things, for some reason.
posted by jammer at 3:31 PM on January 13, 2004

Forgive my insane stupidity, but can ECU's be flashed?
posted by Keyser Soze at 5:06 PM on January 13, 2004

Yes, KS, they can. But (WARNING: Extremely simple summary) the actuall program on an ECU is encrypted. In order to effectively flash a modern ECU you first need to break the encryption on it. This takes no small degree of effort. I'm currently hoping someone will crack the ECU on my model of car, because no one has done it yet and if you want to change anything, you either have to use a piggyback computer which lies to the ECU ("boom boxes" ... because its easy to blow your engine with them), or hack in an ECU from a previous model with a home made adapter kit (huge kludge).

Manufacturers these days often issue ECU reflashes to fix various problems in their cars.
posted by jammer at 7:39 PM on January 13, 2004

My speedometer on my 95 Jeep GC stopped functioning properly (they stopped using cables to measure speed a long time ago apparently).

Depending on the model car I wouldn't necessarily say a long time ago (although I don't know on the jeep). I know I had a 95 escort that had a speedo cable (although in that case it turned out it was the speedo head that went, not the cable).
posted by piper28 at 9:14 PM on January 13, 2004