TP14809 E
1225 New York Avenue, NW – Suite 300
Washington, DC 20005-6165
Phone: 202/638-7825
Fax: 202/737-3742
Andrew Spoerri
Senior Research Analyst
Motor Carrier – Motor Vehicle Safety Directorate
Transport Canada
Safety and Security
Place de Ville
Ottawa, Canada
K1A ON8
November 13, 2007
Via e-mail: spoerra@tc.gc.ca
Dear Mr. Spoerri,
This responds to your September 17, 2007 letter asking us to respond to a series of questions related to speed limiter technical and tampering issues. The Truck Manufacturers Association's (TMA) members include all the major North American manufacturers of medium and heavy trucks greater than 8,845 kg (19,500 lbs.). TMA represents the following companies: Ford Motor Company, Freightliner Trucks, General Motors Corporation, International Truck and Engine Corporation, Isuzu Commercial Truck of America, Inc., Kenworth Truck Company, Mack Trucks, Inc., Peterbilt Motors Company, Sterling Truck Company, Volvo Trucks North America, and Western Star Trucks.
Our responses to your questions are attached to this e-mail. If you have additional questions or wish further clarification of any of the responses, we would be happy to meet with you by phone or in person. Please do not hesitate to contact me in this regard.
Sincerely,
Robert M. Clarke
President
Speed Limiters - Technical and Tampering Issues Responses of the Truck Manufacturers Association
General:
- Trucking interests on both sides of the border suggest that engine and truck manufacturers are generally supportive of proposals to mandate speed limiters in heavy trucks. Views?
At this time, we believe a great deal more information is needed before a reasoned decision can be made on this issue. The Truck Manufacturers Association (TMA) supports proposals that are demonstrated to provide safety benefits and are practicable. We believe this proposal has flaws, especially in terms of its practicality. Nevertheless, we look forward to the results of Transport Canada's studies in this regard. Speed limiters are available options on nearly all trucks equipped with electronically controlled engines. Specifying a vehicle speed limit setting is one tool that is available on all vehicles equipped with electronic engines that can be used by our customers to optimize their fuel economy. As a result, for fuel economy or other business reasons, a significant proportion of trucking fleets voluntarily set their road speed governors to 70mph or less. More voluntary decisions like this, along with increased efforts to enforce existing posted speed limits would save even more fuel.
- Are all model year 1995 and newer diesel engine-equipped trucks (with gross vehicle weigh rating greater than 11,000 kg) manufactured in North America equipped with an electronic speed limiting device?
Generally, nearly all are equipped with electronic engine control modules which have the capability to be programmed to limit the vehicle's road speed. However, some model year vehicles as new as 2003 were built with mechanically controlled engines that do not include an electronic vehicle speed limiting system.
If not, what is the cost to retrofit a truck? We are not aware of any manufacturers that make an electronic road speed governor for a mechanically controlled diesel engine today.
Are there any electro-mechanical or mechanical speed limiters still in use in on-road applications? Some vehicles built before 1999 were equipped with these type speed limiters. If they are still operating, inspectors could come across one. All newly manufactured vehicles use electronically controlled engines that include the road speed limiter functionality.
- We understand that there are approximately15-20 different models of electronic control modules (ECM) available on the market. Do all speed limiters function essentially the same in that it is integrated with the ECM and receives a speed related signal from the driveline (typically the output shaft) and the vehicle road speed is then limited accordingly?
Each engine manufacturer has specific designs for their ECMs. You are generally correct about how they function. A transmission output shaft rotational speed input signal is transmitted to the engine ECM. In order to make use of that data, other variables must be defined in the ECM including: transmission output shaft pulses per revolution, tire rolling radius, and rear axle gear ratio.
- Are there any industry / technical standards or compatibility requirements with speed limiters (e.g. quality, OBDII port, shop tool interfacing, etc)?
Most medium and heavy duty trucks are equipped with a diagnostic connector featuring SAE J1939 and/or SAE J1587 connectivity. The industry is rapidly moving from the J1587 data bus to the J1939 data bus for diagnostic communications with major components like the engine ECM. Although the connection is common, each engine manufacturer has their own proprietary software to access and change settings in the ECM's of their engines. This software is periodically changed and is frequently updated once a given version of it is published. These updates and changes are made available to licensed users of the proprietary diagnostic software Diagnostic equipment from non-OEM suppliers is also available. The cost of these devices varies significantly presumably due to differences in quality and functionality.
- Are there speed limiters that allow drivers to temporarily over-speed (e.g. to safety pass another vehicle)?
Not on level ground. When going downhill, driver braking will be required after fuel shutoff to control vehicle speed.
- What is the potential impact on vehicle fuel economy, durability and maintenance if a truck spec'd to cruise within a set range (i.e. 110-120 km/h) is subsequently speed limited outside of that range (i.e. 105 km/h)?
There is no direct answer for this question. If a truck's power train (engine, transmission rear axles and tires) is specified to maximize fuel economy and is prevented from operating in that range due to speed limiting, there is likely to be a reduction in fuel economy. Fuel economy is greatly dependant on how a vehicle is operated so it is conceivable that any reduction or improvement of fuel economy resulting from a reduced maximum speed limit may be negated depending on how a driver's behavior is modified. For instance, if a speed limiter setting is changed, the corresponding engine speed at top vehicle speed will change as well. This may or may not be a more fuel efficient point as it could cause the engine to over-rev or lug that, in turn, could encourage the driver to downshift, which sets up a whole different set of conditions and possibilities. The net effect will vary from vehicle to vehicle. As previously mentioned, customers often specify drivetrain and aerodynamic components and systems to maximize their fuel economy for their unique application.
Changing / reading the speed setting:
- What are the software/hardware requirements to set or change the speed limiter setting? How do they differ across engine manufacturers and engine models?
Each engine manufacturer does this differently. It is accomplished using the same communications capabilities used for engine diagnostics. Engine manufacturers sell diagnostic and maintenance tools that provide the ability to maintain the calibration of the vehicle's speed function and the vehicle speed signal to accommodate changes in tire size or rear axle ratio. Typically access to the speed limiter setting and related calibration parameters are protected by a password that is given to the owner of the vehicle when it is purchased.
- Can a driver adjust the speed setting from inside the cab? If so, how and what's involved (e.g. equipment, cost)? Can it be done remotely via GPS from a trucking company's headquarters?
A driver/owner equipped with a diagnostic tool could connect to the diagnostic port in the cab and adjust the 'maximum road speed' parameter setting if it is not password protected. The software to do this would cost about $450, while the connectors and other hardware needed would cost about $650-$700. The ability to make these changes remotely, via GPS, does not exist at this time.
- Can a hand-held or wireless PDA be used to read the speed setting?
Several aftermarket diagnostic tools are small hand-held devices. These currently access to the ECM through a hardwired connection to the SAE diagnostic connector. Some manufacturers have developed and offer wireless systems to transmit various maintenance related variables (e.g. engine oil pressure) that originate in the ECM, however customer acceptance has been weak due to cost. Presumably, the speed limiter setting could be wirelessly transmitted as well, but that is not done now. Keep in mind, however, that this setting – by itself, does not control vehicle top speed. As previously noted, other parameters (rear axle ratio and tire rolling radius) are required to calculate vehicle road speed and therefore affect the actual vehicle top speed. In order to determine if the setting was correct a catalog of those variable settings – specific to each vehicle, would be needed. It would then be necessary to determine if tires of the correct size were fitted to the vehicle, as well as the rear axle ratio.
Can the PDA be programmed to lock-out other ECM readings?
The answer is specific to, and dependent upon the architecture and design of each engine manufacturer's software. Presumably, this could be accomplished at some unknown cost.
- Would roadside verification of the speed limiter setting only show the current setting or would information on previous settings be accessible?
For the most part, the only information available would be the current setting. One manufacturer has a counter feature that can indicate how many times the setting had been changed, but it would not indicate what those settings were.
- Can the vehicle maximum speed be permanently set (i.e. hard-wired) by the engine manufacturer and any speed limiter setting equal to or lower than this maximum adjusted with the appropriate OEM software?
ECMs use flash technology for non-volatile storage of data and program instructions, which includes the speed limiter setting. Strict interpretations of "fixed" and "nonprogrammable", or "hard-wired" as you are terming it, would likely obsolete current ECM hardware designs. Various security features are currently being used, or could be added to enable manufacturers to control programming access to parameters such as vehicle speed limit, tire RPM and rear axle ratio. However, if the security was too restrictive and a customer requested a change, it would put manufacturers in a very difficult position relative to establishing the veracity and appropriateness of that request.
What are the implications for engine and truck manufacturers under this scenario?
Manufacturers could be required to receive some type of formal affidavit from the owner verifying the legitimacy of the change request, but manufactures could be overwhelmed with requests as well as the record-keeping requirement. There would still be no assurance that requests were, in fact, legitimate/accurate. Who would be liable for discrepancies? When, if ever, would enforcement officials make use of all this information stored by manufacturers?
Tampering:
- In general terms, to what extent are speed limiters tamper-resistant? What measures has industry taken to address the tamper-resistancy of the speed limiter?
The speed limit setting is secured with a vehicle unique password that is given to the owner of the vehicle. The owner of the vehicle can then change the password to one of their choosing. The vehicle owner controlling and limiting access to the password is a key principle in preventing improper changes. Up to this point, there has been no need to take extraordinary steps to attempt to make the speed limiter setting tamper-resistant. Significant numbers of carriers choose to set the level at or below 70 mph - our survey indicates over 50 percent of Class 7 & 8 trucks sold have this setting. These carriers typically manage the operation of their vehicles and drivers very well and would likely take appropriate steps to correct instances involving unauthorized changes to the setting. We don't foresee any possible way to make such a system completely tamper-proof since we provide the capability to update and change the speed limit setting and other parameters such as tire size and axle ratios.
- What are some of the more common tampering practices (e.g. re-programming, changing sensor outputs, gearing ratios, tire dimensions)? Others?
Tampering with the vehicle speed limit setting or one of the associated parameters is not believed to be common place and we are not aware of any common tampering practices.
- Can the speed setting be adjusted without the proper OEM-supplied equipment (interface, software, etc)? No
- Can one determine specifics on if/when the speed limiters setting was tampered with?
As previously mentioned in our response to question 9, and assuming the speed limiter setting was set to an established value, the only way to check for tampering would be to physically check the other related vehicle parameters and ensure that those parameters were entered into the ECM.
- Do you have any proprietary, legal or company confidentiality issues relating to enforcement personnel potentially accessing ECM data to determine the speed setting and/or who tampered with the speed setting?
No, as long as access can be restricted to only the "need to know" information.
- What new ECM technology is being developed to reduce tampering?
The ECM technology used for speed limiters has been in existence for many years and is performing satisfactorily as evidenced by no customer demand to change the system. Therefore, there have been no efforts to increase the level of security. Any changes in security level would increase the costs of the systems.
Will there ever be a "tamper-proof" speed limiter?
A fully tamper-proof system is highly unlikely. See our response to questions 3, 7, 9, and 12.
- To what degree will efforts to improve the tamper-resistancy of speed limiters increase the costs to truck buyers?
Direct costs would depend upon the level of security and the specific requirements of any legislative or regulatory proposal that was put forward. TMA members are most concerned with the definition that might be applied to a "tamper proof" maximum road speed setting. If this definition of "tamper proof" includes controlling of the parameters like tire RPM and axle ratio then the infrastructure required to control these changes could be very costly since it would require engine suppliers to alter their base engine programming specifically for individual markets and it might require significant changes in manufacturing processes (at the time of manufacture, an engine is not yet dedicated to a particular vehicle or jurisdictional market). Implementation of tamper resistance could also potentially create significant costs for carriers that subsequently needed to legitimately change the setting – for whatever reason. Any requirements that imposed record keeping obligations and/or significant process changes on engine and/or vehicle manufacturers would add substantial costs and burden.
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Two North LaSalle Street |
November 8, 2007
Via E-mail: spoerra@tc.gc.ca
Andrew Spoerri
Senior Research Analyst
Carrier - Road Safety & Motor Vehicle Regulation
Transport Canada
Place de Ville (ASFBM), Ottawa, Ontario K1A 0N8
Dear Mr. Spoerri:
Re:
Speed Limiters – Technical and Tampering Issues
Questions for Truck & Engine Manufacturers
The Engine Manufacturers Association is responding to the September 17, 2007 request for information regarding the technical limitations and tampering issues associated with electronic speed limiting devices on heavy trucks.
Among EMA's members are the major manufacturers of heavy-duty diesel engines that are used in heavy trucks. We appreciate the opportunity to comment and would like to offer the following general comments on this issue as a preface to our attached response to the specific Transport Canada technical questions.
EMA's members are strong supporters of efforts to promote safe and efficient vehicle operation. Toward that end, engine manufacturers offer road speed limiting as a customer configurable feature available on all modern electronically controlled heavy duty on highway engines. Since engine manufacturers are already providing road speed limiting capabilities on these new engines, clearly there is little to be gained by requiring manufacturers to offer this feature.
We are strongly opposed to any proposal that would require manufacturers to "hardwire" a limit specific to a particular jurisdiction (even if that limit is consistent within all of Canada). Such a proposal is unworkable for a number of reasons:
- Speed limiter settings operate on the basis of an engine/vehicle interface and are dependant upon a number of variables outside of the control of the engine manufacturer.
- Engine manufacturers do not and cannot know the vehicle configurations in which their engines will be installed.
- Engine manufacturers do not and cannot know the jurisdictions in which their engines will be operating.
- Engines are designed and produced for North American and global markets.
EMA does not support, nor do we oppose the imposition of regulations on owners to require the use of technology currently available on modern electronically controlled engines i.e. the road speed limit software feature to program a given maximum speed. However, the burden of compliance with any such requirement to utilize this feature must be placed only on the owner of the vehicle. Only the owner knows if and when their vehicle will be operating in a particular jurisdiction in which such a requirement exists, and control over the road speed limit resides completely with the owner.
However, it must be noted that the enforcement and expense of an operator rule is complicated and compounded by a number of factors:
- Multiple hardware / software configurations for each engine manufacturer.
- Continually updated versions of software.
- Lack of a catalogue of software-hardware-engine compatibility.
- Inability to access speed limiter settings and inputs in a standardized manner.
In general, EMA prefers voluntary, incentivized measures rather than regulatory mandates, particularly when the costs and associated burdens of the regulation may not be justified by the potential benefits and when the objectives can be achieved through voluntary measures.
EMA would be pleased to meet with you to discuss this issue further. Please do not hesitate to contact me if you have any questions or would like to arrange a meeting.
Sincerely,
Dawn E. Friest
General:
- Trucking interests on both sides of the border suggest that engine and truck manufacturers are generally supportive of proposals to mandate speed limiters in heavy trucks. Views?
This statement does not accurately reflect the views of engine manufacturers.
EMA's members are strong supporters of efforts to promote safe and efficient vehicle operation. Toward that end, engine manufacturers offer road speed limiting as a customer configurable feature available on all modern electronically controlled engines. Since engine manufacturers are already providing road speed limiting capabilities on all new engines, clearly there is little to be gained by requiring manufacturers to offer this option.
Moreover, we are strongly opposed to any proposal that would require manufacturers to "hardwire" a limit specific to a particular jurisdiction. Such a proposal is unworkable because engine manufacturers do not and cannot know the vehicle configurations in which their engines will be installed or, the jurisdictions in which their engines will be operating. Engines are designed and produced for North American and global markets. A requirement to "lock in" a particular setting at the engine or vehicle manufacturer level is unrealistic, unachievable and ignores the realities of the production of engines and vehicles for the global market. EMA strongly opposes any approach which requires a limit to be "hardwired" or set at the manufacturer level.
EMA does not support, nor do we oppose the imposition of regulations on owners to require the use of technology currently available on modern electronically controlled engines i.e. the road speed limit software feature to program a given maximum speed. However, the burden of compliance with any such requirement to utilize this feature must be placed only on the owner of the vehicle. Only the owner knows if and when their vehicle will be operating in a particular jurisdiction in which such a requirement exists, and control over the road speed limit resides completely with the owner.
In general, EMA prefers voluntary, incentivized measures rather than regulatory mandates, particularly when the costs and associated burdens of the regulation may not be justified by the potential benefits and when the objectives can be achieved through voluntary measures. The voluntary use of speed limiters is widespread in the industry, and of course, all jurisdictions have posted legal speed limits fully enforceable by existing law enforcement. Education and training regarding the potential benefits of speed limiters and lower vehicle speeds may be the most cost-effective means to reach the portion of the industry not utilizing or not equipped with speed limiters.
- Are all model year 1995 and newer diesel engine-equipped trucks (with gross vehicle weigh rating greater than 11,000 kg) manufactured in North America equipped with an electronic speed limiting device? If not, what is the cost to retrofit a truck? Are there any electro-mechanical or mechanical speed limiters still in use in on-road applications?
All electronically controlled model year 1995 and newer diesel engine-equipped trucks are equipped with speed limiting software which could be enabled and set by the owner of the vehicle. However, some model year 1995 and newer (as new as 2003 model year) diesel engine-equipped trucks were built with mechanically controlled engines that do not include a vehicle speed limiting system. In some cases these vehicles were equipped not to exceed a given target speed by the choice of tire size, rear axle ratio, transmission top gear ratio, and the engine's governed speed. Retrofitting vehicles equipped with mechanically controlled engines would be difficult, because there are no known manufacturers that make an electronic road speed governor for a mechanically controlled diesel engine today. The development of a retrofit approach for mechanical engines would likely be cost-prohibitive. It is simply not feasible to add an electronic road speed limiter to mechanically controlled engines at this time.
- We understand that there are approximately15-20 different models of electronic control modules (ECM) available on the market. Do all speed limiters function essentially the same in that it is integrated with the ECM and receives a speed related signal from the driveline (typically the output shaft) and the vehicle road speed is then limited accordingly?
This characterization is generally correct. The engine ECM is calibrated by the vehicle manufacturer, dealer, and/or owner to reflect the choices of tire size, rear axle ratio, and transmission top gear ratio for the road speed limit function to operate correctly. This calibration of the vehicle speed signal is also used by heavy duty vehicle speedometers which rely on the engine's calibration of the vehicle speed signal to display vehicle speed to the driver. The accuracy of the speed limiter setting is dependant upon the accurate capture of these variables which are unknown at the time of the manufacture of the engine. This is one of a number of reasons that hardcoding a limit at the engine level is impossible.
- Are there any industry / technical standards or compatibility requirements with speed limiters (e.g. quality, OBDII port, shop tool interfacing, etc)?
There are many industry standards, incorporated into engine ECMs, that relate to the vehicle speed sensor signal, data, and diagnostics provided by speed limiting systems. TMC RP 123 defined a convention for speed signals. Signals from transmission drive shafts are standardized at 16 pulses per revolution, but many engines do not require that the signal contain exactly 16 pulses and can utilize other conventions. Multiplexed signals from an electronically controlled transmission (transmission output shaft speed, r/s) and the ABS (wheel speed, r/s) are also used to provide the raw speed signal to the engine, typically using J1939-71.
Electronically controlled HD Engines in North America have traditionally relied on SAE J1587 and SAE J1939-73 for diagnostic services. Some HD engines employ automotive standards and will use SAE J1979 or an ISO diagnostic standard (e.g. ISO 9141 and ISO 14230). Both SAE J1587 and SAE J1939-71 define telemetry to show the calibrated or active vehicle speed limit, and most heavy duty engines provide this information. TMC RP1202 defines a 6-pin connector for SAE J1587 and SAE J1939-13 defines a 9-pin connector for J1939-73 and J1587. J1939-13 and RP1202 provide location guidelines for the diagnostic connectors. These guidelines typically locate the connector inside the cab on the driver's side of the vehicle. Vehicles using automotive standards will most likely use the SAE J1962 connector.
Prior to 13 CCR 1971.1, compliance to SAE J1939 and J1587 was voluntary, based on customer and industry association requests. When the California Air Resources Board adopted 13 CCR 1971.1 (Heavy-Duty On Board Diagnostics,) ARB required HD engines to provide standardized OBD diagnostic communications using CAN beginning in 2013. Both SAE J1939-73 and J1979 (using ISO 15765-4) are accepted. US EPA regulations have been proposed using these same conventions. Within these standards an engine manufacturer may be required to diagnose a vehicle speed sensor, when it is used for emissions related functions. 13 CCR 1971.1 does not require engines to provide a calibrated or active vehicle speed limit as emissions related data for review with a scan tool.
In summary, although many components of the speed limit system are standardized, significant elements are not standardized across the industry. As a result, it is not possible to access, in a standardized way, all the information necessary to determine whether a particular vehicle limit setting is in effect and consistent with relevant variables such as vehicle axle ratio and tire size. In particular, no requirement exists for existing or future model year engines to provide access to vehicle speed limits via a generic shop tool interface. Each engine manufacturer uses their own proprietary software to access and change settings in the ECM. In the future, standardized OBD diagnostic communications will be required to access specified information for certain purposes. However, access to speed limiter settings and/or programming does not fall within these requirements.
- Are there speed limiters that allow drivers to temporarily over-speed (e.g. to safety pass another vehicle)?
Most vehicle speed limiting systems do not include a "push to pass" button. Vehicles can coast faster than their vehicle speed limit setting on downhill grades. Some manufacturers have recognized the importance of maintaining momentum in rolling terrain and provide a way to achieve a modest increase in speed over the limit on a downhill slope to provide additional momentum for the next uphill slope. This concept mimics the engine speed overrun performance that was typical of mechanically governed engines, and provides smooth transitions between fueled and non-fueled engine operation at highway speeds.
Some manufacturers offer software that allows the driver to temporarily override the speed limit. In some cases, the vehicle owner sets the allowable over-speed, while other approaches allow a maximum variation around the specific speed setting. There is also a driver reward feature available where the vehicle owner may allow a higher speed limit for drivers with good fuel economy habits. A similar option exists, which allows the cruise control limit to be set higher than the specific speed limiter value to encourage the use of cruise control.
- What is the potential impact on vehicle fuel economy, durability and maintenance if a truck spec'd to cruise within a set range (i.e. 110-120 km/h) is subsequently speed limited outside of that range (i.e. 105 km/h)?
Because heavy-duty vehicles are sold with customized tire sizes, rear axle ratios, and transmission ratio sets, the impact on fuel economy will depend on the individual vehicle configuration and its payload. Although lower vehicle speeds can improve fuel efficiency, when the engine is properly matched with a drive train to operate at lower speeds, slowing down a vehicle that is otherwise optimized at a higher speed may reduce fuel efficiency. For instance, an operator may have to select a lower transmission gear that increases the engine speed to maintain performance while still meeting vehicle speed limits. Also, oil change intervals may be extended with lower engine speeds.
Changing / reading the speed setting:
- What are the software/hardware requirements to set or change the speed limiter setting? How do they differ across engine manufacturers and engine models?
Calibration methods for vehicle speed limiting functions are unique to the individual engine manufacturer. In general the speed limiter functions are part of the engine software and may be password protected. Typically these methods use the communication capabilities provided to communicate engine diagnostics. Each engine manufacturer has unique, proprietary software, diagnostic and maintenance tools that enable access to the vehicle speed settings within certain limits (to accommodate changes in tire size or rear axle ratio and to adjust the maximum vehicle speed). In many cases a laptop PC, technical software and communications adapters and cabling are required to make speed limiter adjustments. So, the software and hardware requirements vary from engine manufacturer to engine manufacturer and the software and hardware (cables, communication adaptors) may also vary between engine models of a particular manufacturer.
As a result, multiple versions of software and hardware would be required to access (set, read or change) the speed limiter settings for all manufacturers. In fact, multiple versions of hardware and software requirements would be required to access all engines from even a single engine manufacturer. The broader the scope of coverage desired (in terms of engine model year), the larger the number of potential software and hardware requirements. With the release of new model year engines and software changes that sometimes occur within model years, software and hardware updates would need to be obtained on a continual basis from all manufacturers.
Another difficulty would be in identifying what specific software version and hardware would be needed for a particular engine. This information is not readily identifiable from a visual inspection of an engine or vehicle. The creation and maintenance of an industry wide catalogue of this information would be difficult and very burdensome and could not be undertaken by industry since the disclosure of this information between manufacturers is objectionable due to confidentiality and competitive concerns.
- Can a driver adjust the speed setting from inside the cab? If so, how and what's involved (e.g. equipment, cost)? Can it be done remotely via GPS from a trucking company's headquarters?
Some manufacturers offer the option for driver adjustment from inside the cab. In general this is through optional software. Dynamic adjustment of a vehicle speed limit has been discussed by industry associations, but no standardized method of operation has been defined for all vehicles to use, whether based on Geo-fencing or satellite communications. The ability to adjust remotely does not exist at this time.
- Can a hand-held or wireless PDA be used to read the speed setting? Can the PDA be programmed to lock-out other ECM readings?
Some manufacturers can use a hand-held PDA to read the speed setting on some model year engines, provided the device contains the appropriate proprietary software. Wireless operation is cost-prohibitive and is not used at this time. In other cases, a PDA is not compatible and only a laptop computer with the appropriate proprietary software can be used. It is unlikely that a device could be designed and built to interface with all makes and models on a uniform basis. In addition, displaying the engine ECM calibration data for the tire size, rear axle ratio and transmission top gear ratio may be impractical for all makes and models, because this calibration information is in a protocol that is unique to the manufacturer. It would then be necessary to compare these settings with the actual configuration of the vehicle to determine whether the settings/inputs were consistent with the actual vehicle configuration. Without all of the information on the relevant variables and inputs, it would not be possible to determine the accuracy of the speed limiter setting. The ability to lock-out other ECM settings is dependant upon the software and varies from manufacturer to manufacturer. However, existing programming does not widely include this ability.
- Would roadside verification of the speed limiter setting only show the current setting or would information on previous settings be accessible?
Typically, only the current setting would be available. EMA is not aware of any engine manufacturer software which stores the previous settings.
- Can the vehicle maximum speed be permanently set (i.e. hard-wired) by the engine manufacturer and any speed limiter setting equal to or lower than this maximum adjusted with the appropriate OEM software? What are the implications for engine and truck manufacturers under this scenario?
At the time of manufacture of a new engine, engine manufacturers have no way of knowing which engines are destined for vehicles that may operate in Canada. Engines are manufactured for North American and global markets with the same software and hardware in engines destined for Canada, the U.S. and in many instances globally. Emissions regulations are harmonized between the U.S. and Canada and emissions regulations worldwide are moving towards harmonization. Unique Canadian product simply does not exist and global products are becoming more prevalent. The realities of the market and the manufacturing process alone, would make this hard-wire approach impossible, unless it were applied to all engines sold in North America, and in some instances globally, thereby creating a de facto North American or global limit based on a Canadian or Provincial requirement. Existing manufacturing and design processes, and customer support simply cannot accommodate this type of differentiation of software and hardware. The cost of altering existing practices to accommodate such differentiation would impose significant, monumental costs on the industry. EMA strongly opposes any such requirement.
Moreover, for speed limiting to work properly it is not only necessary that the limit be programmed into the engine control module, but that the computer module receive a vehicle speed signal. The vehicle speed signal is provided by the vehicle manufacturer, an entity that is typically separate from the engine manufacturer. Further, at the time that the engine is installed in a vehicle the system must be properly programmed with the vehicle axle ratio, tire size and other variables in order to properly interpret the signal from the vehicle speed sensor. Since engine manufacturers do not provide the vehicle speed sensor and do not know the values of the variables needed to properly evaluate the speed sensor signal at the time that the engine is sold, the engine manufacturer is unable to complete the programming of the vehicle speed limiting system before the engine is sold and leaves his control. This being the case, it is impossible for engine manufacturers to hard code a limit on vehicles.
Hard-coding a limit at the vehicle level also raises significant issues. Differences in proposed fixed values among jurisdictions would create significant service and administrative problems for vehicle owners and manufacturers in assisting customers seeking to use the same equipment in more than one jurisdiction. Servicing engines across jurisdictional lines would create questions about how to administratively control the application of the proper fixed value in a particular vehicle. A vehicle could be purchased in a jurisdiction with a required speed setting for operation outside of that jurisdiction or vice versa. Many vehicles operate in more than one Province and there is significant cross-border traffic between Canada, the U.S. and Mexico. Imposing such a requirement on new vehicles could have the unintended impact of delaying the purchase of new vehicles and the turnover of older, higher-emitting engines (for example, by those operators who might be inconvenienced by such a limit because of multi-jurisdictional operation.)
It should also be noted that although many owners possess the software to enable them to change the speed limiter settings as desired, other operators do not have this ability and must rely on the dealer to access the settings if changes are desired. Generally, this service is not performed without an associated charge. The cost of the software and hardware to enable changes by the owner is not insignificant ($500 - $1000). Fleets that purchase large quantities of engines and vehicles often get the benefit of the software and hardware as part of their purchase. This is not usually the case with purchases of single vehicles and engines.
Tampering:
- In general terms, to what extent are speed limiters tamper-resistant? What measures has industry taken to address the tamper-resistancy of the speed limiter?
Generally, the speed limiter settings have a similar level of security or password protection as other parameters that are trimmable via the software tool. Adjustment of the speed settings and speed calibration for service is secured with a customer password or PIN that must be supplied to authorize the data modification. Vehicle manufacturers provide the vehicle owner with the initial customer password, which the vehicle owner may alter. Like many other computer software applications, controlling and limiting access to the password is a key principle in preventing improper modification of these settings. In some cases, software performs rationality checks of the vehicle speed input signal and parameters such as gear ratio and engine speed. If values are not within an expected range, a fault code is logged.
- What are some of the more common tampering practices (e.g. re-programming, changing sensor outputs, gearing ratios, tire dimensions)? Others?
Tampering can be accomplished by any means in which the inputs to the speed limiter settings (including tire size, transmission ratio, axle ratio) do not match the actual vehicle configuration, or by changing the selected speed limit. This can be accomplished by altering the vehicle components (tires, axle, transmission), by altering the settings, or by altering the signals. For example, the vehicle speed signal can be altered using a software tool to change ECM settings for gear ratio, tire size, or number of teeth on the speed sensing wheel.
- Can the speed setting be adjusted without the proper OEM-supplied equipment (interface, software, etc)?
Adjustment of speed settings and vehicle speed signal calibration cannot be performed without the OEM-supplied or designed equipment.
- Can one determine specifics on if/when the speed limiters setting was tampered with?
The current vehicle speed limit setting can be accessed via PDA or a laptop, equipped the appropriate engine manufacturers proprietary software. A physical inspection of the vehicle could be performed to confirm the rolling radius of the vehicle's tires, the rear axle ratio, and the transmission ratios from the transmission's data plate to compare to the data in the engine ECM. Mismatched data might be an indicator of tampering or might be the result of human error (when the values were input for example, or at the time of vehicle assembly). There is no way to determine when tampering might have taken place.
- Do you have any proprietary, legal or company confidentiality issues relating to enforcement personnel potentially accessing ECM data to determine the speed setting and/or who tampered with the speed setting?
Existing vehicle speed control systems do not provide positive data on changes that may be construed as tampering, or provide proof that tampering did occur. Errors such as entering the wrong data are indistinguishable from malicious acts. Many engine ECMs provide indications that changes in ECM user data did occur, but do not categorize the data changes as "tampered" or "legitimate." Access to ECM data is controlled via the use of a variety of security protocols and password systems. Generally speaking engine manufacturers prefer to limit the access to engine ECMs in order to reduce the risk of disclosure of confidential business information and trade secrets, including those methods used to prevent tampering in the first place. Access to speed limiter settings would not likely result in exposure of this category of information and EMA does not object to access to speed limiter settings at this level.
- What new ECM technology is being developed to reduce tampering? Will there ever be a "tamper-proof" speed limiter?
Existing speed limiting systems were developed to provide additional value to vehicle owners. They are customer configurable parameters and are protected as such (with an owner controlled password). At this time there is no demand and therefore no need to increase the level of security. Many other engine parameters are accessible only by the engine manufacturer or by dealers with engine manufacturer authorized software. A fully tamper-resistant system is highly unlikely since the speed limiter setting is dependant upon the interaction of a number of variables and access to these inputs is necessary in order to reflect changes to these variables. Adding high levels of development and material expense to provide redundant vehicle speed signal sources and ultra secure calibration methods is not likely to be cost justified.
- To what degree will efforts to improve the tamper-resistancy of speed limiters increase the costs to truck buyers?
Direct costs would depend on the level of security desired and the means attempted to provide the level of security. Even the simplest recalibration or modification of software will have an associated cost. In general, development costs are reflected in the costs of the engine and vehicle to the purchasers.