Digital diagnostics

Bryan Murphy had just grabbed a cup of coffee when the phone rang with the kind of call most truck salesmen dread: a customer down for unexpected repairs. Murphy, general manager of Twin Bridges Truck City, a Volvo dealership in Davenport, IA, expected the worst. This wasn't just any customer. Murphy had personally sold him a new VT 880 just six months ago. So Murphy gripped the phone a little tighter

Bryan Murphy had just grabbed a cup of coffee when the phone rang with the kind of call most truck salesmen dread: a customer down for unexpected repairs.

Murphy, general manager of Twin Bridges Truck City, a Volvo dealership in Davenport, IA, expected the worst. This wasn't just any customer. Murphy had personally sold him a new VT 880 just six months ago. So Murphy gripped the phone a little tighter and prepared for a browbeating.

What came next surprised him — the customer's thanks.

Here's why. “My customer was on the road one night when his cell phone rang,” Murphy says. “On the other end was a technician from Volvo Action Service (VAS) informing him that his truck had a problem and they needed his help to check it out.”

Murphy's customer was completely surprised. “The first thing he asked the technician was, ‘How do you know my cell phone number, much less who I am?’”

The technician knew the customer's cell phone number and name because Murphy had uploaded that information when he activated the Volvo Link Sentry service that came free of charge with the VT 880.

The service constantly monitors onboard computers to track fault codes. If a code is active for more than five minutes, the system sends an alert via the Volvo Link satellite communications channel built into the truck to VAS, where a technician reviews the fault code to determine what, if any, action is necessary.

In this case, a sensor had malfunctioned, causing a “false positive” engine fault code to appear. On the surface, it didn't sound serious. But once the sensor tripped the “check engine light” on the dashboard, the engine would automatically begin to de-rate, thus eventually stranding the trucker on the side of road.

The VAS technician quickly routed Murphy's customer to the closest Volvo dealer — in this case one outside Denver — thanks to Volvo Link's GPS, which provided the truck's location.

The customer arrived at the dealership just as the engine light came on and the truck began slowing down, says Murphy. However, since VAS had already called ahead to the dealership with the owner's name, service issue and parts request, Murphy's customer ended up spending only three hours off the road.

“It's the kind of situation where without that automatic ‘heads up’ from the truck's own diagnostic system, he could have been shut down for eight hours or longer,” Murphy points out. “Instead, the downtime was controlled, avoiding a tow truck and lengthy wait for repairs. In fact, he told me he can't see being without this in the future.”


Plucking data from a truck's own systems — whether via satellite or cellular connection, special handheld tools, or personal computer hook-ups — and using that information to streamline the vehicle maintenance process is what truck makers are after these days, says Bob Dannenberg, chief engineer for International Truck & Engine Corp.'s Class 8 vehicles.

“The key is to get a head start on troubleshooting; that's what diagnostic data helps you do,” he explains. “If you can use telematics to report fault codes … before the truck reaches the shop, that's extremely valuable. You can get the shop technicians ready for that truck's arrival and order the necessary parts beforehand,” says Dannenberg.

“Since most manufacturers can get emergency part orders filled in 24 hours, that head start provided by diagnostic data gets the process moving before the truck is even in the shop,” he adds.

Tom Diefenbaker, director of technical support for Freightliner LLC, points out that a fully integrated electronic system enables technicians to perform a more accurate and faster diagnosis.

“Let's assume a customer has a complaint that the heating element on the driver-side mirror does not operate anymore,” he says. “In the past, the technician would have to trace the signals through the wires, switches, relays, circuit breakers and the heater unit in the mirror to locate the problem.

“In electronically integrated vehicles, the technician can read out the status of the heated mirror switch with the diagnostic tool and can separately power up the heater element of the mirror without even opening the hood of the truck or removing any panels in the dashboard,” Diefenbaker explains.

Even without the telematics link, just speeding up the diagnostic analysis process in the shop pays big dividends, says Mike Dozier, Kenworth Truck Co.'s chief engineer. Like all major OEMs, Kenworth and its sister company Peterbilt Motors offer a proprietary tool for diagnostic code reading.

One of their newest devices is the Electronic Service Analyst (ESA), a computer-based software tool designed by parent company Paccar to diagnose dashboard electronics. According to Landon Proull, Peterbilt's chief engineer, “It enables technicians to review codes stored in the components, verify instrument functions to accurately pinpoint a malfunction, and diagnose potential problems. The ESA interfaces with the vehicle through a special port mounted under the dash and allows technicians to perform diagnostics from outside the cab. Additionally, ESA software creates an event log for a service history of the electrical system.”

Kenworth's Dozier adds, “This helps the customer be confident in knowing the problem has been fixed quickly and the right part has been installed. That, in turn, helps get their trucks back to work faster.”

Getting critical diagnostic information off the truck and into the hands of technicians isn't just the bailiwick of proprietary OEM tools, however. There is also a trend to developing generic service tools.

Delphi Product & Service Solutions, for example, recently developed the DS800 computer-implemented vehicle diagnostic system, which provides a wireless network that enables technicians to remotely access diagnostic information and technical data on an as-needed basis while they work on trucks.

“One of the key attributes of the system is its ability to integrate unlike applications,” says Bill Wrubel, director of sales & marketing for Delphi's Integrated Service Solutions division. “The open architecture platform increases productivity by eliminating inefficiencies in locating technical information, training materials and system integration, as our portable computer tablet is connected to the Internet to provide access to all data, information, programs and applications.”

One of the toughest issues faced by OEMs as they try to improve the flow of diagnostic information is making sure everything on the truck speaks the same language, which is not an easy thing to do.

“Electronic systems are increasingly being developed with coordinated sensors, actuators, microcomputers and information processing units for the engine, drivetrain, suspension, steering and brake systems in next-generation vehicle systems to achieve enhancements in vehicle comfort, feel, fuel efficiency, safety, and maintenance care,” says Siddharth D'Silva, a research engineer with Delphi.

“Such systems can have several interacting software and hardware components, including electronic control units, hydraulic modules, and motor controllers, etc., which in real-time conditions often exhibit dynamic behavior,” he explains. “Unexpected interactions among the software, the hardware, and the environment may lead to situations of potential concern … leading to the need for robust diagnostic strategies.”

Technicians must also be able to interact with the diagnostic information flow, notes Wayne Wissinger, product manager for Mack Trucks. They literally need to tell the vehicle to record certain data sets in order to improve vehicle efficiency and monitor potential trouble spots.

“Part of our V-MAC IV (Vehicle Management And Control-fourth generation) electronic system is designed to allow technicians to track different data sets over time,” he explains. “For example, a service trip lets the service technician view and reset the same data that is in the LOV (life of vehicle) log. If a truck is experiencing a problem, the technician can reset the log and view its results after a test drive or the next time the vehicle stops.”

The V-MAC IV also provides a fault reporter log, which allows the technician to create a trigger event within the system so they can record exactly what's going on when the fault occurs: vehicle speed and engine rpm, as well as pedal and switch positions before and after the fault.


The continuing target for diagnostic information delivery, however, remains the air. In other words, transmitting data via satellite or cellular links from the truck to the maintenance shop in real time, allowing technicians to get a heads-up on problems and thus possibly avert a roadside breakdown.

“With our AWARE vehicle intelligence system, we're expediting critical diagnostic information to the end user via our Internet link — getting it to them via email or even as a test message to their cell phone,” notes Steve Wagestar, International's program manager for the Class 8 ProStar tractor.

“It's all about short-circuiting road problems,” adds Don Philyaw, director of sales and marketing support for Volvo. “It's no longer just about getting diagnostic information from the truck. It's about marrying it with technical expertise when the problem occurs. It's keeping trucks and drivers on the road, making sure the truck operates in the ‘sweet spot’ for the best fuel economy, and making vehicle downtime planned for both scheduled and unscheduled maintenance. That's the value diagnostic information offers us today.”

Vehicle diagnostics from OnStar

The trend to on-board vehicle diagnostics is even extending down to lower GVW trucks. For example, GM's OnStar system, available on some pickups, now offers a vehicle diagnostics feature.

“OnStar Vehicle Diagnostics give us a unique way to stay in touch with customers, but it also provides us with important diagnostic data about our vehicles so that potential issues are identified and addressed quickly,” says Jamie Hresko, vp of GM's North America Quality program.

The diagnostic service works on several levels, says Hresko. First, the vehicle is automatically programmed to send a monthly email to the owner that includes maintenance reminders based on current odometer reading, remaining engine oil-life, plus diagnostic checks of the engine, transmission, anti-lock brakes, and airbag to ensure they are functioning normally.

The second level of the system involves real-time system checks via GM's Goodwrench Remote Diagnostics check program. If drivers have a concern, they press the blue OnStar button and a Goodwrench tech performs a real-time remote diagnostics check of the vehicle.

New capabilities include automatic tire pressure monitoring and emission system compliance — helping owners keep their vehicles in tip- top shape to reduce downtime for maintenance while maximizing fuel efficiency, says Chet Huber, OnStar's president.

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