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On-Board diagnostics and telematics have come of age
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Written by Peter Els, Published by Global Automotive Technology   
Saturday, 21 June 2014
On-Board diagnostics (OBD) have come a long way since VW first introduced the blinking check lamp on their 1969 type 3 fuel-injected models.

The potential of OBD in monitoring and reporting on malfunctions effecting tailpipe emissions was soon recognised, and in 1991 the California Air Resources Board (CARB) required all new vehicles sold in California to have some basic OBD capability. The European Union followed suite in 2001 with the introduction of EOBD for petrol driven vehicles.
The European Union and the United States remain the leaders in Emission control and OBD, with the rest of the world adopting their own standards, generally based on the experience of these 2 regions.

The global implementation of emission standards.

Source: The International Council on Clean Transportation.

A shift in OBD, related to tailpipe emission monitoring and reporting.

With more stringent emission regulation and tighter thresholds, it’s no longer acceptable to merely rely on the Malfunction Indicator Light (MIL) as a means of warning the operator and authorities, that a system or systems have exceeded regulated parameters.

This current system relies heavily on a trip to a verified test centre (commonly known as the Smog Check) every two years to monitor and enforce compliance. This is not only a costly affair (Conservatively $20 to $40 per visit), but also time consuming, especially for the majority of vehicles, that are compliant. OBD-II has successfully driven down emissions, while the proposed OBD-III takes the monitoring and reporting process to the next level – automated reporting through telematics.

Telematics have already gained a foothold with systems such as Mercedes Benz’s Mbrace (Through Hughes Telematics Inc), BMW’s ConnectedDrive (With its roots in BMW’s open source Next Generation Telematics Pattern) and GM’s OnStar system. So one-way vehicle communications (in some cases two-way) are well developed and it’s only a matter of developing the optimum interface between the systems developed for OBD-II and the telematics. Of course a standardised communication protocol will have to be established to operate across vehicle platforms.

The system could be set up to automatically report an emissions problem via a cellular or satellite link the instant the MIL light comes on, or to answer a query from a cellular, satellite or roadside signal as to its current emissions performance status.

OBD-II data, such as Vehicle Speed, RPM, and Fuel Level is already being used by GPS based fleet tracking devices to monitor vehicle idling times, speeding, and over-revving. OBD-II is also monitored to block mobile phones when driving and to record trip data for insurance and tax purposes.

OBD-III will lead to cost savings.

Using cellular communication the cost saving is estimated to be approx 43% on the current Smog Check, and 69% if the vehicle is already equipped with a mobile. Potential OBD-III costs are broken down as follows (Discussed in a 2000 report by Sierra research Inc on the incorporation of wireless into vehicle OBD):

•    $80/ vehicle for the OBD-III hardware (if no Mobile is already fitted)
•    $1/ month for the cellular service.

When considering these savings, there’s no allowance made for the time saved in not having to present a vehicle every 2 years for routine inspection – with OBD-III, only malfunctioning vehicles will be called in. This pro-active system also means malfunctions can be attended to earlier, by so doing improving emissions over the life of the vehicle.

Telematic communication systems available for integration with OBD-III

The essence of OBD-III is to enable vehicles to communicate emission data and status in an automated manner so that rapid repair can be ensured. Radio communication is the obvious choice for this, with 3 proven systems available:

1.)    Short range, ground-based: Low power (Less than 10 mw) or unpowered transponders that communicate with ground-based roadside receivers.
2.)    Long range, satellite-based: Higher power (around 1 Watt) transponders or pagers that communicate with receivers in low earth orbit.
3.)    Long range, ground based: Higher power (around 1 Watt) transponders, pagers or cellular phones that communicate with a ground based network of receivers.

Short range, ground based systems.

These systems have been well tested in applications such as:

  • Automated toll-collection.
  • Traffic information for vehicle operators.
  • Vehicle identification and information (such as truck and cargo information)

During preliminary studies conducted in 1999 the CARB came up with the following costing model:


  • Transponder and fitment costs as Original Equipment is estimated to be in the region of $25 but not exceeding $50.
  • One ground based receiving station would be required for every 2200 vehicles.
  • Based on this, approximately 7,300 stations would be required to service 16 million vehicles.
  • Initial infrastructure costs would be around Mio $80 for the network.
  • Annual operating costs are estimated at Mio $10.

Long range, satellite-based systems

Using this system 2 way communication is possible as currently used by Omnitrac to track commercial vehicles worldwide.
Although the cost of the system is relatively high – at between $100 to $400 per user, it does allow for integrated vehicle tracking without an additional GPS service.

This system was dropped from consideration because of the high cost, and possibly even more importantly, the vehicle tracking capability. Satellite tracking is capable of tracking vehicles over a wide area, raising personal privacy issues WRT information available to government.

Long range, ground based systems.

There are two systems of interest:

Cellular telephone systems:

Ground based cellular systems are well established across most of the globe. Furthermore most OEM’s offer on-board cellular systems for long range ground based communication.

One concern around following this route would be the additional traffic that the network would have to handle. However, this can be brought to manageable levels through configuring OBD-III systems to carry out a status check every 90 days. That would mean 4 calls/ vehicle/ year, with each one lasting no more than 1 second.

With the proliferation of Smart Phones another avenue of communication is opening up; namely, data transfer. This has already found use in on-board infotainment and vehicle security, and lends itself to the telematic requirements of OBD-III.

Obviously the amount of data being transmitted will influence the cost – both from the infrastructure required and the “call” cost. In this regard the data transfer should not exceed 100 bytes, consisting of the following:

  • 17 digit VIN number.
  • Date and time
  • Fault code status
  • Error checking.

This can be reduced to a single bit by implementing:

  • Date/ time stamps (Service providers already use this function for billing)
  • Unique calling unit identification. These consist of the devices manufacturers identification number (ESN), and the mobile ID number (MIN) related to a specific network. This information can be centrally processed to tie up with the vehicle VIN number, instead of having this data transmitted.
  • Using unused space on the service providers control channels. This space is limited to 55 bytes which could be sufficient for OBD-III communication.

It is estimated that the annual service cost for this data service would be approximately $18. This coupled to a “stripped down” cell phone costing in the region of $50, would appear to be a viable solution.

One way alert systems

These systems are equipped with transmitters only and are commonly used as emergency locator beacons for ships and aircraft, as well as for transmitting data from weather balloons.

In the OBD context, the “one way alert” system would be used to transmit relevant data regarding VIN, status, fault codes, date and time.

Although this meets the requirement it’s very limited in any form of added value, which can be achieved by the other systems. The fact that it’s only one-way communication means that a simple, but important, function such as switching on the MIL to alert an operator that the vehicle has exceeded the threshold would not be possible.

A test model

A prototype system built by GM Hughes Electronics was evaluated by ARB using a roadside transmitter to interrogate vehicles as they pass by.

The system used ultra low power 10 milliwatt receiver stations and 1 milliwatt transmitters (which is about 1,000 times less power than a typical cellular telephone) with a broadcast frequency of 915 Mhz. The system was capable of retrieving information from 8 lanes of bumper-to-bumper traffic moving at speeds of up to 100 mph (160 kmh)!

When the vehicle receiver hears the query signal from a stationary or portable roadside transmitter, it transmits back an answer in the form of the vehicle's 17-digit VIN number plus an "okay" signal or any trouble codes that may be present.

The information can then be used to identify vehicles that are in violation of clean air statutes so a notice can be sent that repairs and/or smog testing is required. Or, the information could be used on the spot to identify vehicles for a pullover roadside emissions check or issuing an emissions citation.

Challenges in implementing OBD-III

Although the telematics technology currently exists, and is already being widely used, the application to OBD-III faces several challenges:

The primary obstacle is that of implementation cost. Irrespective of which system is chosen the support infrastructure is either non-existent or would need to be expanded to cope with the additional traffic.

Time to implementation is another challenge. Not only the time to establish the infrastructure (Best case timing to be 2 years), but also to have the OBD-III Telematics integrated and tested in vehicles. This is also estimated to require a full 24 months.

The final, and possibly greatest challenge, will come from the public’s perception that the OBD-III system may constitute an invasion of privacy (In the US in particular as the Fourth Amendment to the U.S. Constitution protects the rights of individuals against unreasonable searches and seizures).

Although CARB has investigated these legal issues and believes that the U.S. Supreme Court has made it clear that vehicles are subject to a diminished expectation of privacy compared to a persons’ residence or personal effects, several rights groups have indicated their intention to challenge should this ever be legislated.

It can also be argued that the use of transponder based technology will not enable the state to obtain more information than it could by simply increasing the frequency of inspections.

One method of making OBD-III more acceptable to motorists is by asking them to sign a consent form (when purchasing the vehicle) allowing the state to query the OBD-III system, and informing motorists that they would save money by not having to Smog Check their vehicle every two years.

To further reduce public resistance and share costs, this system could also be incorporated into other telematics-based systems, i.e., vehicle navigation or anti-theft vehicle location systems, automated tolling etc.

Current Telematics applications:

All European and American OEM’s (Or their suppliers) have well developed telematics systems already in production.

GM’s OnStar system already has a function whereby motorists can be alerted of a fault and directed to a dealer for repair.

Other systems, such as the Mercedes Benz Mbrace takes this one step further by allowing drivers to connect with their vehicles via an iPhone(TM) or BlackBerry(TM). This allows them to do such things as remotely lock or unlock their vehicles; or locate their vehicles in crowded parking lots or on city streets through a map representation on their smart phones.

Of particular interest is BMW’s open source NGTP (Next Generation Telematics Pattern). This adopted a new approach for delivering over-the-air services to in-vehicle devices and handsets alike, with the focus on open interfaces across the entire service delivery chain.

NGTP’s developers set the following six objectives:

1.    Provide a technology-neutral pattern and consistent interface and protocol for telematics services;
2.    Reduce barriers to collaboration and implementation;
3.    Enable adoption of new technologies as they come online;
4.    Support legacy systems for connectivity throughout the service life of a vehicle;
5.    Gain wide acceptance and encourage innovation through an open approach;
6.    Increase the value proposition for vehicle manufacturers, service providers, content providers, and motorists.

There’s no doubt that OBD-III is moving in the right direction, but for it to be truly viable it needs to offer a wider package by keying into existing vehicle telematics and systems.

About the Author:

Peter ElsMr. Peter Els is an automotive engineer in South Africa. With 30 years experience in the OEM and first tier supplier environment, he has held managerial positions in engineering, after sales service and marketing.
He often shares his experience as a contributor to leading publications such as Automotive IQ./em>

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