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Diagnostics on the fly

The blinking text on the dispatcher's screen means it's an emergency message. Truck 2323 is getting a low-pressure reading from its inside right rear drive tire. The dispatcher calls up the tire's pressure readings for the last 48 hours — it's a slow leak that's just crossed the warning threshold. Taking the truck's GPS location, he finds a tire repair shop in the fleet's national network that's only

The blinking text on the dispatcher's screen means it's an emergency message. Truck 2323 is getting a low-pressure reading from its inside right rear drive tire. The dispatcher calls up the tire's pressure readings for the last 48 hours — it's a slow leak that's just crossed the warning threshold. Taking the truck's GPS location, he finds a tire repair shop in the fleet's national network that's only 20 miles down the road. A phone call confirms that the shop is open and able to handle a tire repair, and a message to the driver gives him directions and a P.O. number for the repair. The tire is repaired and the truck is back on the road without the loss of the tire, the cost of emergency roadside service or a missed delivery window.

Possible? Absolutely. Today's trucks already carry much of the technology needed to support such a scenario, and the rest is well within current technology's limits. In fact, you could substitute any electronically monitored component on a truck for the tire and such remote diagnosis is still perfectly feasible with existing technology.

Practical? That question isn't so easy to answer. There's one remote diagnostic system already on the market, another will be announced in October, and nearly all truck manufacturers and wireless service providers are looking at similar systems. The stumbling block is whether fleets really want such remote diagnostic capability, or rather whether they can find ways to justify its cost.

The ability to monitor fault codes sent over a vehicle's J1708 data bus has been offered for some time by all of the wireless communications providers with dedicated services for the trucking industry. “We introduced satellite-based fault-code monitoring in 1992,” says Tom Doyle, vp-OEM business development for Qualcomm Wireless Business Solutions. “We were just listening to our customers. In that timeframe, many thought remote fault-code monitoring was valuable.”

Fleets were dealing with the first generations of electronically controlled engines, which meant learning to use plug-in diagnostic readers. “It was a natural extension for customers to ask for remote access,” says Doyle. Also, as an early generation technology, the electronic controls “were not as reliable as they are today, so monitoring them was more important,” he adds.

However, as the wireless system began gathering other data such as vehicle speed, fuel consumption and location, and as the electronically controlled engine technology became more reliable, “the focus shifted,” says Doyle. “Remote connectivity to a fleet's vehicles became more focused on operational data than fault-code monitoring” because that data offered greater opportunity for quicker payback.

“But even though operational data has dominated the picture for our customers, that doesn't mean other things aren't going on,” he notes.

“Fleets are not willing to pay for (remote diagnostics) by itself,” agrees Carlo Nardini, director of technical support for Freightliner LLC. “However, once you have a (wireless) communications platform, you have the opportunity to take advantage of that platform for other uses including remote diagnostics.”

An agreement announced last month between AT&T Wireless and Freightliner's parent, DaimlerChrysler, is intended to provide that platform. The two will develop a “telematics strategy” for the company's U.S. automotive customers, including its truck customers. Once that communications pipeline is in place, it would be relatively easy to use it to monitor vehicle systems and perform diagnostics, says Nardini.

Dr. Chuck Carpenter, Aether Systems, recently surveyed fleets on what kinds of remote diagnostic capabilities they feel they need or want. “The response was a mixed bag,” says Carpenter. “There was no clear suggestion of one killer application.”

Currently, Aether's MobileMax2 wireless data system can monitor 25 fault codes carried by either the J1708 or J1939 data buses, receiving one message a day reporting the status of those monitored fault codes. The fleets pick the 25 to be tracked out of more than 250 fault codes that can be sent over the two data buses, and they also have the ability to change the bundle of codes monitored daily.

Carpenter's survey asked the Mobile Max2 fleets if they wanted the ability to poll a vehicle for any one of those 25 parameters instead of having to wait for the daily report.

“It was a 50/50 split, and even those who said they would use it expected the frequency to be very small,” he reports. For example, one fleet with 700 trucks said it might poll individual trucks for specific fault codes only a dozen times in a month. And even those interested in on-demand reports said they preferred to get information on all 25 parameters at once, rather than a single parameter per request, according to Carpenter.

The fleets were far more interested in being able “to change the parameters tracked for a single tractor over the web from their dispatch system,” he says. “They really are looking for that flexibility.”

Chris McDonald, vp of CF&T Concrete Pumping in Hayward, CA, is a good example of fleet ambiguity over remote diagnostics. Eight months ago the company took delivery of a new Mack pumper equipped with TruckLink, a wireless diagnostic and vehicle location system from McCarney Technologies.

The aftermarket system detects, captures, stores and forwards fault warnings from any electronically controlled system linked to the J1708 data bus. The messages are transmitted via analog or digital cell phone networks to a diagnostic hot line, which relays them on to the fleet. The system can also predict impending system failures, according to McCarney, and can be fitted with voice and text-messaging options for the driver.

In the eight months the truck has been in service, McDonald has received one call from the hot line. “They'd gotten a low coolant level warning,” he says. “I called up the truck on my laptop, which lets me see its location, as well as things like engine and transmission temperatures. Everything seemed okay, so I let the truck stay (at the work site), and we took care of the coolant when it got back that night.”

Although that one incident prevented CF&T from losing a day's revenue, McDonald says he probably won't put the system on the fleet's other 29 trucks. “If we were an over-the-road fleet, I might, but we see our trucks every day.” Frequent location updates might also make the system more attractive, he says, with the diagnostic capabilities offering a nice bonus.

The remote diagnostic system can be justified, however, if a fleet has the right application. Hurley Transportation Cos. of Phoenix operates 75 trucks. Only one has been fitted with the TruckLink system, but it's become an essential part of that truck's service, according to Bob Campbell, general manager of Hurley's distribution group.

“We have one tractor — a new Mack Vision — that picks up the early edition of a national newspaper in Riverside, California, at 6 p.m.,” says Campbell. “The load has to be in Phoenix by midnight for home delivery the next morning. That's a six-hour run, which makes it pretty tight.”

Early last year an alternator failure caused Hurley to miss its delivery window, which not only displeased the customer, but also resulted in lost revenue. About 12 months ago, the fleet installed the remote diagnostic system to guard against another service failure.

“The monitor would have told us that we had a problem before it became a failure,” says Campbell. For that particular route, “the system is absolutely cost-effective.”

With most of its other trucks in local delivery routes, Hurley can't say the same thing for the rest of its fleet. But for that one distribution run, remote diagnostics provides great value, according to Campbell.

While fleets may be lukewarm about remote diagnostics right now, circumstances in the near future could make it far more attractive, if not turn it into a standard fleet tool.

For example, new safety regulations could bring vehicle systems that would make remote diagnostics far more useful. Congress is currently considering legislation that would require tire-pressure monitoring on commercial vehicles.

“If that happens, you'll have that (tire) information available for diagnostics, and I'd expect rapid movement to a remote system,” says Doyle. “There's also another wave of electronics systems coming, and with more data (from those systems) available on the truck, the value of monitoring increases.”

The spread of the Internet is also spurring development of Web-based diagnostic applications built on the Internet's TCP/IP standards, adds Nardini, who points out that Freightliner is working on a system. Such Internet applications are easily adapted to wireless systems, he says.

Initially these Web-based shop systems would be used with wireless links “for emergency service,” says Nardini. For example, a technician could use a remote truck's data bus information to create an oil-temperature or rpm gauge on his computer screen. “The shop could do a preliminary assessment using that monitor, if someone gets stuck on the road,” he explains.

Eventually, Nardini sees such systems spreading to more routine chores such as changing vehicle operating parameters in real-time to meet fleet requirements for specific road or cargo conditions. “It might also be possible to intercept diagnostic faults and automatically schedule a vehicle into a service facility, but that would require a whole new infrastructure ‘to catch the ball’ and act on that information,” he adds.

Advances in wireless data service could also affect the cost/benefit ratio of remote diagnostics, leading to far more sophisticated applications that go well beyond current capabilities, explains Doyle.

“We're right on the edge of high data-rate and wireless Internet services,” he says. “They'll give us the ability to send large blocks of data and to have rapid interactions with mobile units. Prognostics are impractical today because it's too expensive to put the computing power and data storage you need on a vehicle. But (high-speed wireless) could make prognostics cost-effective because you can connect a vehicle to all the off-board computing power and data storage you need.”

Whatever develops in remote diagnostics over the next few years, it will only see widespread adoption if it helps fleets increase their bottom line or productivity.

“We've all done a great job in selling the need for wireless data, but sometimes we've fallen short on making that data useful to the end users,” says Carpenter. “Fleets aren't looking for fault codes. They want something action-based, e.g., this truck needs to be serviced for this reason at this location. And they want it delivered wirelessly to the person who needs to know it.”

Only when remote diagnostics can deliver on that promise will fleets judge it practical as well as possible.

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