Scanning for Errors

OBD II changed maintenance forever--OBD III is set to do the same.

The industrial revolution glutted tailpipes and smokestacks in the name of progress, and it wasn't until 1971, with the federal Clean Air Act, that the automotive industry was harnessed with a regulatory standard which asked for air-friendly accountability. Legislation for emissions standards has since become as thick as the layer of smog over LA, and it's still here, in all its tangled history, winking slyly as a Check Engine light every time we start our vehicles.

The EPA spearheaded this campaign for regulation and explains the continuous adjustments. According to their website,, on-board diagnostic (OBD) systems were implemented as a response to the inherent environmental flaws in motor vehicles: "Despite numerous improvements in automotive technology, motor vehicles continue to be a major source of air pollution, accounting for approximately 77 percent of CO2 and 45 percent of ozone-causing nitrogen oxide (NOX) in our nation's air."

OBD was set up to curtail this pollution problem. Its essential purpose is to act as a monitoring system which has the capability of measuring tailpipe emissions and alerting the driver of any malfunction of the emission-control system. The current standard, OBD-II, is the second tier, but not the last. Any car manufactured after MY 1995 was required to be equipped with OBD-II, which monitors a wide range of emission controls and lights the 'check engine' light if a problem is detected.

Leave it to the effusive power of technology to not let it stop with only emissions. Not surprisingly, OBD has since begun to blanket almost everything that can be monitored or managed within an automobile.


John Frala, associate professor of alternative transport technologies at Rio Hondo College in Whittier, California, has been deeply embedded in the technology for over thirty years, starting when GM outfitted its '74 Chevrolet Vega with the first semblance of an on-board diagnostic system. He has seen diagnostic systems grow from exclusively emission-related to what we have today in OBD-II, and he anticipates further technological advancements: "the new standard will be faster, with more data, so you can really pick the finites like low tires, temperatures… (It will be) even more precise with the goal of ultimate efficiency," Frala says.

OBD-II reduced the automotive choices to two protocols: J1850 and ISO-9141-2, which still created a bevy of avenues in which the data could be processed, inspected and maintained. Frala, who also does dealer training for American Honda, explains the link between today's standards and those of the near future: "OBD-II standards are now being expanded to a new communication protocol combining J1939 and ISO 9141-B speeds to what many have dubbed the 'OBD-III' operating system."

At the center of this OBD-III system is the Controlled Area Network (CAN), which has been mandated by the EPA to be in all cars manufactured in 2008 and after. This new system addresses some of the inadequacies of OBD-II in the sense that it is an interoperable computer system that can manage a number of different elements under one protocol. The CAN system has practical benefits in terms of economizing fleet time and cost, especially for things like efficiency and routing in public transportation.

"Now the automotive CAN network is being used in transit bus operations for features like GPS tracking to identify where a bus is and how long it will take to pick up the fare-paying customer. As the bus is operating, they can update information related to engine and transmission operation through the GPS transponder without removing the bus from service," Frala says.


While the technology itself must be broadly implemented, industry suppliers have responded with widely varying products which accomplish the goals set out by the EPA in myriad ways. B&B Electronics is one of many of the companies flooding the market with a diagnostic scan tool. B&B's director of business development, Matt Williams, sees their particular product, Auto Tap, as the best balance between the most important elements behind OBD-II utility: "functionality vs. cost."

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