OEMs Fine-Tune Telematics
Collecting vehicle data can help fleet managers pinpoint potential problems, as well as help manufacturers benchmark truck performance.
By Stephen Bennett
When the "check engine" light comes on, fleet maintenance departments increasingly want to know more than why it lit up. For years, "diagnostic trouble codes" generated by electronic control modules on many trucks have helped mechanics identify a problem, fix it and get a truck back into service promptly. Some OEMs are working on ways to use the data to detect patterns that could enable them to forecast, and possibly fend off, system and component malfunctions or breakdowns.
While electronic data recording or storage varies somewhat from OEM to OEM, the basics are often similar, in that electronic control modules for major systems and components - the engine, transmission, anti-lock braking system - also collect data about their performance.
The information that may be recorded is voluminous - coolant temperature, power takeoff engagement time and idle time are just some examples - and can be consulted regularly to enhance fleet maintenance practices, in turn leading to a boost in overall vehicle uptime or productivity, according to original equipment manufacturers.
For example, Isuzu's diesel-powered trucks for model-year 2008 have a data recording module that pulls data from various sensors and control modules. Software within the Isuzu Diagnostic Service System scan tool, typically a laptop, sorts the data into easily understood screens and reports, said Micah Embry, a marketing manager for Isuzu Commercial Truck of America.
The DRM records more than 100 data types, he said, including fuel rate collected over time, as well as distance traveled (for the calculation of fuel consumption); vehicle speed; engine speed; gear range; throttle position; coolant temperature; PTO engagement time; idle time; start cycles; air temperature; air pressure; boost pressure; exhaust brake usage; fuel temperature; diesel particulate filter regeneration; and cycle time for exhaust gas recirculation.
The DRM is located under the instrument panel. When a vehicle arrives at a dealer's service department, mechanics can download the information into the dealer's database and that of the OEM, said Todd Bloom, vice president of marketing for Isuzu.
"We can compare that vehicle's current performance to its past performance and also to other vehicles within the fleet or other vehicles in the overall database," Bloom said.
Isuzu can use such a diagnostic database to forecast when a system or component is most likely to need servicing or replacement, thereby performing preventive maintenance only when necessary, Bloom said.
The incorporation of a DRM on 2008 trucks is part of a larger project to provide telematics capabilities on Isuzu vehicles in the future, Bloom said.
Other OEMs have developed similar systems. For instance, a data recording and diagnostic reporting system that Navistar Electronics developed for International Truck and Engine Corp.'s medium-duty trucks uses the vehicles' computer network to collect data and cellular technology to transmit it.
Major electrical subsystems on International vehicles include control modules for the engine, transmission and anti-lock braking system, all of which are connected by computer networks on the vehicle, said Robert Dannenberg, Navistar Electronics' chief engineer. The networks form data links between the major subsystems.
Just as a cable connects a home computer and a printer, International has a cable between the engine controller, transmission controller, anti-lock braking system, gauge cluster and other components or systems and a box installed in the cab. The box contains a cellular modem for sending data over a Verizon digital network to International's servers for presentation on a Web site where fleet managers can access the information in report form.
With each module storing fault codes, the traditional means of reading them have been to use "off-board" diagnostic tools, typically a scan tool or a laptop computer, which at times could be inconvenient, Dannenberg said. "You always had to find the vehicle and hook up to it to retrieve these trouble codes," he said.
In 2005, International introduced a wireless communication or telematics device that automates the data retrieval and transmission processes with a data recording device on the vehicle that is connected to the vehicle network.
The device is "constantly watching what is communicated between all the modules," Dannenberg said. The device also contains a cellphone modem - each vehicle has its own cellphone number - enabling the transmission of the data over a Verizon network, he said. The system can be programmed to send selected data every 15 minutes; data deemed less urgent can be programmed for transmission daily, say at 3 a.m.
The information goes into a database that International hosts. The fleet user who has signed up for the service gets a user identification and password to log onto a Web site and view the information about his fleet vehicles, Dannenberg said. In cases where there is an operating malfunction, the system can notify the fleet via the Web site, e-mail a text message to a cellphone number or "any combination thereof," Dannenberg said.
Alerts would be sent in cases where the diagnostic code signals a problem, such as an engine malfunction, a failed alternator or low battery, Dannenberg said. The system supports preventive maintenance as well, by sending notification when a truck is due for service. A fleet maintenance manager can set the interval based on miles, engine operating hours or gallons of fuel consumed.
"If a fleet has trucks that do most of their work in idle - using [PTO] - they don't want set intervals based on miles," he said.
OEMs' Methods, Goals Vary
Each OEM's approach to collecting and using diagnostic data differs.
"In our case, we do not have a DRM at all," said Robert Aquaro, vice president, product assurance, for Mitsubishi Fuso Truck of America. "There really isn't a master. We are reading data codes from the engine electronic control module, or the transmission electronic control unit or even the anti-lock brake module."
The list of monitored data includes throttle position via a sensor, engine operating temperature and diesel particulate filter pressures. "The system is essentially concerned with emissions and any failure that can cause the engine to go out of emissions spec," Aquaro said.
If a coolant temperature sensor fails, for example, the engine control module will record the failure in the form of a diagnostic code, and the "check engine" light will be illuminated on the instrument panel. At that time, the truck should go into the dealer for service so the technician can "read" the code with a scan tool and find out why the light came on, Aquaro said.
"It's essentially as simple as that," he said. "The light comes on. Why?"
The scan tool that Fuso supplies to its dealer technicians is a Panasonic Toughbook with a touch screen and proprietary software. "The mechanic brings it right to the truck" and plugs it into the vehicle, Aquaro said. The software program asks the mechanic which module he wants to scan and then indicates that the diagnostic code triggered the light because the temperature sensor is defective, for example.
"It is pretty straightforward," Aquaro said. "These systems are designed to assist the technician in getting the truck back in service more quickly should something go wrong."
A telematics system that is widely recognized in the automotive market is General Motors' OnStar, which is exclusive to GM vehicles. The OnStar system on passenger vehicles can provide an e-mailed monthly diagnostics report. It also is able to "interrogate" the vehicle's system of electronic control modules and determine, for example, tire pressures, said Steven Matsil, global vehicle chief engineer for medium-duty commercial trucks at General Motors Corp. "It is reaching down to your vehicle and pulling out information that is provided to you in summary form," he said.
The system also is programmed with an algorithm that can calculate a vehicle's remaining useful oil life. It might indicate, for example, that 50% of that oil life remains. "It won't give you a date, because useful oil life depends on the duty cycle" - how the vehicle has been driven, highway miles, the effects of hot weather, the effects of towing and so on, Matsil said.
GM is working to develop a version of OnStar "that would appeal to fleets," he said. "The key here is that it's got to be a cost-effective package," Matsil said, since the cost to fleets would be on a per-vehicle basis. "We have to show them that it's going to improve their downtime. We continue to work on it."
Stephen Bennett, a freelance writer based in Connecticut, has extensive experience writing about technology issues.
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