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A Fleet of Data in U.S. Vehicles

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By: Melissa C. Lott and Ian Kalin, Presidential Innovation Fellow, U.S. Department of Energy

In the early 1970s, auto manufacturers faced the challenge of how to ensure compliance with new U.S. emissions standards without sacrificing vehicle performance. As a result, they largely turned to electronically controlled fuel feed and ignition systems. And, with the addition of “On-Board Diagnostics,” a new river of digital information began to flow through the nation’s vehicles.

When first introduced, On-Board Diagnostics (OBD) systems were governed by few standards. Sensors measured engine performance and then automakers used these data to create digital controls  that automatically adjust vehicle sub-systems in order to provide required pollution control. The information gathered by the sensors was also used for some basic diagnostic purposes. But, a lack of universal standards led to varying system specifications between vehicle manufacturers, inhibiting widespread use of these data.

OBD-II port location

In 1988, in response to this disjointed approach, the Society of Automotive Engineers (SAE) recommended a standard connector plug and set of diagnostic test signals. The U.S. Environmental Protection Agency adapted most of the standards from SAE for On-Board Diagnostic systems.  Eight years later, a set of expanded standards and practices was adopted by the EPA and California Air Resources Board and dubbed “OBD-II.”

All cars built in the U.S. since 1996 have an OBD-II port, which gives the vehicle owner – and their mechanic – access to information on the health and operation of key systems throughout the vehicle’s controller area network. The data port (see photo) can transmit both proprietary manufacturer data and open data.

The confidential information streams include data on systems like anti-lock brakes and the air bags, which are valuable for manufacturers to monitor real-world system performance.  The open data streams  are required to contain information critical to diagnosing emissions-related issues but manufacturers also include additional, valuable information.  Some typical parameters would include the following (varying slightly by vehicle make): ignition status (on/off), engine speed, vehicle speed, fuel level, fuel consumed since restart, odometer reading, distance covered since restart, longitude and latitude, fuel efficiency, condition based maintenance, brake pedal status  (on/off), headlamp status (on/off), high beam status (on/off), windshield wiper status (on/off), ABS status (on/off), accelerator pedal position, torque at transmission, parking brake status (on/off), door open status (open/closed), steering wheel angle, transmission gear, and vehicle emissions status.

The raw data is simply a digital stream (bunch of 1’s and 0’s) that needs to be converted from something the computer understands to something a human can read for it to be useful. One example would be the Ford OpenXC system, a new open hardware and open software platform that supports public technology innovation, which displays, the raw dataas a long text file of acronyms and readings (see examples, below).  And, for the majority of vehicles, these data are not being stored in a live manner by any commercial web technology cloud service.   The local data storage is minimal and primarily used for emissions testing.  This leaves a wealth of valuable information literally sitting – underutilized – in individual vehicles.

Of course, other digital data streams currently exist within vehicles and are increasingly being utilized by innovators.  For example, over the past decade, navigation systems have adapted to new technologies including mobile phones. Today, nearly all smart phones have some type of navigation mobile app, which travels with the vehicle owner (and, in turn, with the vehicle). Other digital systems are pushing cars to perform more laptop-like actions, such as Entune from Toyota and Sync from Ford. One can see the slow evolution of the business models for connecting these vehicle data streams and product platforms..

The addition of On-Board Diagnostics to the U.S. vehicle fleet was catalyzed by federal environmental regulations. With it, a new river of data began to flow. As a result of this data stream, a world of new possibilities was introduced for innovators and entrepreneurs who can see the opportunity that exists.

Photo Credit:

1. Photo of OBD-II port in dashboard by KlausNahr and used under this Creative Commons license.

2. Screen captures of data streams from Wikimedia Commons.

Melissa C. Lott About the Author: An engineer and researcher who works at the intersection of energy, environment, technology, and policy. Follow on Twitter @mclott.

The views expressed are those of the author and are not necessarily those of Scientific American.

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  1. 1. MoEnergySci 4:05 pm 12/5/2012

    If I wanted to download my own data from my car how far back would the data go? Months or years or just a day or two? I would like to learn more. Thanks.

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  2. 2. jtdwyer 1:04 am 12/6/2012

    “The addition of On-Board Diagnostics to the U.S. vehicle fleet was catalyzed by federal environmental regulations. With it, a new river of data began to flow. As a result of this data stream, a world of new possibilities was introduced for innovators and entrepreneurs who can see the opportunity that exists.”

    I’m just an old information systems analyst, but just one or two examples of this “new world of opportunities” would help me understand what you’re getting at – I have no idea…

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  3. 3. MoEnergySci 9:48 am 12/6/2012

    Does Onstar use the data stored in this part of the car to detect things like airbags going off and sudden stops?

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  4. 4. Wrmurraytx 12:28 pm 12/6/2012

    @MoEnergySci – That’s exactly how Onstar works, they also detect impacts based on accelerometer readings from sensors around the car.

    @JTDwyer – There is a very active community of “makers” that are working with the ODBII port and the data network, CANBUS to develop aftermarket add ons, control systems and geegaws for cars. (Go search Arduino and CANBUS for the little microcontrollers) I work for a large supplier to the auto industry and we use the same system for developing many of the parts and electronics that go into your vehicle.

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  5. 5. MoEnergySci 5:30 am 12/7/2012

    @Wrmurraytx – thanks. any idea how many sensors are in today’s cars? I wonder if there’s a big difference between cars that have Onstar and those that don’t. Or is this maybe a legal requirement too like OBD-II?

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