Reader Question: Where Did OBD Come From?

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Here’s the latest reader question, along with my reply!

Nunz asks: T’was just wondering how exactly it came to be that the OBD diagnostic system became universal across all brands and makes of cars. I mean, was it via government mandate, or via the voluntary cooperation of competing auto manufacturers? (I should know this…but I don’t! Although, I smell gov’t mandates on a grand multi-continental scale!).

My reply: The first scannable onboard diagnostics systems appeared in the late ’60s – VW was a pioneer, it used such a system with the Bosch-injected ’68 Fastback/Squareback. Other manufacturers added similar systems of their own, as they switched from carbs to EFI.

It was just a diagnostic tool – as it is today. Many included a “check engine” light to alert the driver to the need for service.

But each manufacturer had its own (proprietary) system.

CA (of course) was the first state to mandate OBD in the early ’90s.

The SAE (along with others) then recommended a standardized system – with a universal diagnostic plug-in port. This became mandatory for all passenger vehicles in beginning in ’96.

While I loathe and resent the government, OBD does have some good points. A simple (and universal) scan tool that you can purchase for around $100 makes isolating a problem/fault much easier. The key thing is to get a reader that will decipher the codes rather than just give you a code.

. . .

Got a question about cars – or anything else? Click on the “ask Eric” link and send ’em in!

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  1. Heres one thing I never get – perhaps Eric or some of the wiser commentators here will have an idea. Whenever I’ve been to a deal with a dealership (mostly BMW lately) they always quote retarded prices. When I challenge them why, and how they are charging more per hour than a surgeon or something, they always say that they have to invest thousands for specialist diagnostic equipment that company requires for proper fixing the cars.

    Now given that as you say all cars have the same OBD port that can be connected to a 50 pound Bluetooth OBD dongle, and most codes can be found on the internet via a simple google search (if they are not already in the app you use to connect to the dongle), is there really any such “specialist equipment”, or is it all just BS to justify their prices?

    • Well Nasir (I know you wanted a wiser commenter- but if you’re willing to settle for the 4th Stooge…)

      It’s like this: The dealers do have some more sophisticated diagnostic equipment. Some of it isn’t all that expensive [from a professional’s point of view]- like a pro quality OBD II reader that can do everything, like ABS codes, and test various modules and even get into the signals that the car’s computer is putting out- they only cost about $5K these days- Hardly comparable to the 1/2-1 Million bucks and many years of study and internship of a surgeon….

      Then, the dealers do have some proprietary stuff… For instance, a Chrysler dealer has a proprietary device which can reset the master cylinder and brake system after brake bleeding, which, as far as I know, no one else has….but again, hardly comparable to a surgeon.

      And what’s more, the “techs” working at the dealerships often don’t know how/aren’t very good at using the info from all of that equipment- or just plain don’t care. When you go to the stealership, the service-writer is the guy you deal with- and he often makes his determination of what your car needs without even looking at the car or doing any tests- He gets a commission for selling you as many (and as expensive as possible) repairs as he can.

      What it really comes down to, is who actually works on your car. There are some good dealer techs out there- who are competent and conscientious….but your odds of getting such a one- well- it’s just a crap-shoot.

      What it comes down to, is that the insane dealer prices are so because the dealerships make most of their money in the service department; most of the customers are ignorant; and the dealers have a lot of employees and real-estate and such to support, plus make a very hefty profit on repairs. They figure: “If you’re there, it’s because you’ve nowhere else to go, and are thus a chicken ready to be plucked, or just don’t care”.

      In the case of cars like BMWs, it’s even worse, because BMWs have a lot of quirks and oddities that generallu only those who work on a lot of BMWs are familiar with- so many independent shops (unless they specialize in German cars) can’t do a lot with a BMW- or can’t do it competently or efficiently- basically, cars like BMWs and VWs require a specialist. (Although such are probably a lot more common there in Yerp than here in ‘Merca).

    • And PS, Nasir,

      Even on simpler cars, you really can’t just read the cade and replace a part, and viola! It’s fixed. (Well..sometimes that’ll work- but it’s a crap-shoot). The codes are really just a starting point; clues in the general direction of where to look.

      For instance: I had a Jeep Grand Chimpanzee(Cherokee)…it was running really rough and had no power and was bucking and spitting. I plugged in ye olde scanner, and it threw a code for something like “Coil – circuit B”.
      Well, after some internet sleuthing and some tests with a multimeter, I discovered the source of the problem: The crank position sensor (Which, being on top of the transmission housing on those things is a BEAR to get at!)- which is a very common problem on those thangs. Now you would think that it would have thrown a code that said “Crank Position sensor”….and it might have, had the sensor actually been dead- but what I discovered when changing it, was that the problem was that the sensor was actually loose in it’s bore, and was bobbing around, thus giving an erratic signal to the coil- thus generating the “Coil – circuit B” code.

      So it can be tricky- but a LITTLE intelligence and some experience, and a good deal of conscientiousness mainly- and it’s hardly the stuff of surgery.

      • Hey nunz,

        Thanks for your comments – Given you do all this work you are definitely more capable than me when it comes to such matters.

        Totally agree with you about how dealers make a good chunk of their profit from service these days (along with pushing finance deals).

        Furthermore you are also right about how the dealer techs are not very good. My guy is an ex bmw guy, who has all their certifications (including the highest rolls ones). He left and went independent because as you can say he didn’t like the way many there worked, just plug in the computer, change whatever parts are relevant to the code it gives, send the guy away with the max bill possible. And if it doesn’t fix the problem well then you can bill more for something else. And as you say most of it is led by the guys at the desk who are meant to maximise sales and utilisation of the staff….

        So at the end of the day unless it’s warranty work, prob no point going to a dealer…. especially if you can find a good independent guy…

  2. My daughter had a ~1997(?) Subaru and the codes were unreadable by anybody except Subaru dealer who charged $130 even way back then (2004). It was just a money pit and she subsequently scrapped it.

    I’ve got an OBD2 reader from O’Reilly’s for $65 and then you can look up the code on the interweb and usually find out exactly what’s wrong based mostly on other folks’ misadventures. Even the dealers sometime can’t figure it out and charge a bundle for “fixing” the wrong thing.

    • Yeah, Anon,

      Getting the code(s) is really just the first step in diagnosis. Figuring out why the code was thrown…..that’s really the diagnostic process. Luckily, now even many of the cheap scanners (like mine!) allow you to look at live data, etc. to see things like fuel trim and timing, and all…and with that and a multimeter, even a shade-tree mechanic can do a pretty decent sleuth job, if he cares enough to.

      The stealerships? They don’t care. They just want to make money by selling you work and throwing parts at it. The amazing thing is, they get paid even if they can’t fix it…so it’s all gravy for them- and if ya take ’em to court, you’ll lose, unless you have a really good mechanic there with you to testify and explain how they screwed up.

      What a freaking system! Just another reason to never buy new.

  3. Thanks, Eric!

    Yes, the OBD system is “one of those things”, which certainly makes life easier for anyone who works on cars- although Uncle has no right to mandate such things- and of course, like most Uncle-mandated things, it also ends up (whether by design or happenstance- but I suspect the former) fostering more surveillance and control- as it so easily morphed into something which enables “black boxes” and after-the-fact data retrieval; and even things like the remote control of cars; drive-by-wire; and “self-driving” cars (All enabled by the humble data provided by what started as merely [supposedly] a diagnostic tool and electronic engine control scheme).

    I’ll tell ya one thing though- that period from the mid 80’s, when electronic fuel-injection first started to proliferate, up until the mid 90’s when OBD II came around, was sure a bummer- especially for do-it-yerselfers!

    Oh, and wouldn’t ya know it: Just Googled something, and it turns out that OBD II was first mandated by CA. (as you said)…to facilitate their CARB nonsense and emissions testing! Figures.. There ALWAYS has to be evil motives behind everything the gov’t does… But like you also stated, at least we do get some handy benefits from this one. I couldn’t imagine living without my scanner!

  4. Look up the torque application on an android phone. The base version is free, and can be paired with a $20 bluetooth adaptor for a combo that can display real time information, as well as look up any code online. Seriously the best setup out there. If you want better, you will need to spend $4000 at snap-on.

    • I have a $53 Autel scanner that’s amazing. It does graphing and everything! I hope they keep making ones like this for those of us who refrain from using cellphones…. (But such seem to be on the endangered list these days, just like self-contained MP3-players!)

      • Nunz, what are you, anti-technology or something? Stop clinging to your ancient, polluting technology, and drop a grand on the latest iphone like the rest of us…

        Just kidding, of course.

        I still have an MP3 player too. Because it has 6 physical buttons. And when I drive, I like to keep my eyes on the road, unlike the safety hypocrites, and change songs by feeling the buttons. Impossible with a touchscreen.

        • Brandon, you’re just like me! I NEVER take my eyes off the road. Wouldn’t have a car with a touch screen. I’m a freakin’ Mr. Magoo, but I’ve only been in one accident in my life (100% other guys fault- he blew a stop sign) in 36 years of driving….’cause I keep my eyes [errr…’eye’] on the road.

          Hey, hey! I’m getting with the times! I’m thinking of getting two tin cans and a string! Although I might wait till someone comes out with an amplifier for the end of the can…so I can go stringless![I’m sure if I watch Gilligan’s Island enough, I can figure out how to do it]


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