March 23, 2009 11:35 AM, EDT

Technicians to Face More Fault Codes With Use of OBDs, Engine Makers Say

By Dan Leone, Staff Reporter

This story appears in the March 23 print edition of Transport Topics. Click here to subscribe today.

Truck technicians next year will have to deal with a pronounced increase in engine fault codes because of the onboard diagnostics systems added to 2010 and later model engines, engine makers said.

“In the past, the technician effectively had two fault codes that he could work with on a sensor,” said Andrew Plant, manager of support system development for Detroit Diesel Corp. “Now with OBD, that same sensor doesn’t have two codes — it has five codes.”

U.S. Environmental Protection Agency regulations require 2010 and later model-year engines to be bundled with diagnostics that use an array of sensors to police emission-control systems (3-9, p. 4).

If a truck’s emissions of nitrogen oxides or particulate matter exceed certain thresholds, the OBD system must alert the driver via an in-cab light.

Additional fault codes appear because OBD systems monitor emission performance, a condition to which technicians “were effectively blind” before EPA’s mandate, Plant said.

The upside for technicians is that no new equipment is required to read and interpret the new fault codes that OBD systems will generate when an emission level drifts out of compliance, Plant said.

“The technician’s job hasn’t changed pre-OBD and post-OBD,” Plant pointed out. “He uses the same voltmeter, the same troubleshooting guide and the same laptop computer” to process fault codes.

Nevertheless, technicians at Detroit Diesel’s distributors and dealerships will need more training to deal with the additional complexities OBD brings to the table, Plant said.

To that end, Detroit Diesel, which has about 22,000 technicians in the field, crafted a Web-based training module that it will require all of its technicians to complete.

Besides the Web-based module, one technician from each Detroit Diesel service facility will be required to attend a second level of training.

“We ask every location to have ‘one doctor in the house,’ one expert,” Plant said. “We process those people. We bring them into the class with the instructor.”

Plant said Detroit Diesel hopes to have 60% of its technicians trained “before the product is issued to the field.”

Detroit Diesel, Detroit, is part of Daimler Trucks North America. The company makes engines for Daimler’s Freightliner and Western Star trucks.

Navistar Inc., maker of International trucks, is also leaning on software to help train field technicians.

“For 2010, we’re going to have two Web-based training programs,” said Mark Hobson, field service manager for Navistar. “One will cover the changes in the 2010 engine versus the current engine and the second will cover any changes in the diagnostics.”

While technicians will receive additional training to familiarize them with OBD, they will “still use the same hardware and software we already use” to process fault codes, said Etienne van Niekerk, Navistar’s service education manager.

Navistar has about 7,000 field technicians in its network, van Niekerk said. Those that require OBD training should receive it within a month of 2010 trucks hitting the road, he added.

Navistar is the only engine maker in the North American market that is not using selective catalytic reduction to meet EPA’s 2010 emission cuts. However, the company still must comply with the agency’s OBD mandate.

The OBD standards for SCR engines vary little from Navistar’s enhanced EGR approach, Navistar representatives said. Most notably, SCR engines have specific sensor and diagnostic technologies associated with their urea distribution systems.

Tim Shick, Navistar’s director of marketing, said the company’s enhanced EGR did not require new sensors to comply with the OBD mandate.

Other engine makers, including Cummins Inc., Volvo Trucks North America and Paccar Inc., had not responded by press time to a request for comment.

Automobiles have used OBD systems since the mid-1990s. Heavy-duty diesel engines will use these systems for the first time in 2010.

As a result, EPA has decided on a gradual phase-in of the OBD mandate. For example, only one engine family per manufacturer will have to use OBD in 2010.

Moreover, OBD systems in 2010 will not be required to trigger a warning light until regulated emissions rise to more than double EPA 2010 levels, the agency said.

By 2019, all engine families from all manufacturers will have to use OBD systems, and detection thresholds will tighten so that any breach of the 2010 emissions standard will trigger a warning light, EPA said.