One of the most disheartening things a driver can see, other than the red flashing light of a police car in the rear-view mirror, is the 'Service Engine Soon' warning on the instrument panel.
Many times when the service light illuminates the engine seems to run just fine, leaving the driver to wonder, 'Should I stop now or can it wait?'
A definitive answer requires a time-consuming trip to the service department, which sometimes means that the owner delays important service work.
But automakers are looking at ways of using vehicles' existing technology to immediately diagnose the problem, tell the driver how serious it is, and fix it as quickly as possible - all strategies designed to boost customer satisfaction.
The key to this plan is getting a technician to communicate with the car while it is on the road.
Such service techniques may seem as futuristic as warp drive from 'Star Trek.' But in reality, the technologies that are the building blocks of such a system already are installed in some vehicles today. And using them to link a vehicle with the service department may be in the near future.
Here's how such a system might work:
If the engine service light comes on, the driver pushes a dedicated button on a cellular telephone.
The call goes to a service center. An operator at the center talks with the driver about the problem, and routes the call to either the nearest dealer of that franchise, or the franchised dealer of the caller's choice.
Once connected with the dealership, the caller talks with a service technician, then presses another button on the cellular telephone. This links the phone with the vehicle's engine control network, and sends the data to the technician.
The technician runs the data through a diagnostic terminal to read trouble codes and can perform tests to identify the problem.
If the problem can be fixed with a software change, the technician could download the new software into the engine control computer via the telephone link. If the problem requires a visit to the dealership, the technician can schedule a service appointment and order parts in advance.
When General Motors introduced its OnStar system last year, executives said that enabling the vehicle to signal when it was malfunctioning was a possibility for future uses of the system.
Now, however, OnStar representatives decline to talk about such a use for the system, saying it is considered a competitive issue related to future product plans.
Ford Motor Co., which offers the RESCU system on the Lincoln Continental, also would not discuss service information, saying it is related to future product plans.
But one supplier was happy to talk.
'We're promoting servicing as a use for our data transfer technology, but we don't have anybody online yet.' said Bob Drury, manager of advanced traffic information service business concepts for Siemens Automotive in Auburn Hills, Mich.
Siemens has developed a proprietary method for sending large 'packets' of data in quick bursts over cellular phones. The data packets were developed for a lower-cost vehicle navigation system Siemens plans to introduce in 1998. But the technology can be used easily for other applications, such as service information, Drury said.
Not only could a technician download data from a vehicle that was on the road, Drury said, but if the repair is merely a software change, the technician could upload the new program to the car and the owner would not even have to visit the dealership.
Such a system could be a boon for automakers by lowering warranty costs and enabling greater compliance with recall campaigns for software-related changes to engine and vehicle-control computers. The repair could even be done in the middle of the night. The service center would call up the car and download the new software, Drury said.
The process of transmitting data to and from vehicles is known as telematics, which is getting a big boost as more automakers install navigation and emergency services systems in their vehicles. Every time a Cadillac owner uses OnStar, or a Lincoln Continental owner calls for assistance from RESCU, data from the Global Positioning System satellite receiver in the car is sent via modem over the cellular phone to pinpoint the car's location for the operator at the response center.
On vehicles with OnStar, data movement can be a two-way process. The service center operator can command the vehicle to flash its lights if the owner is having a hard time finding the car in a crowded parking lot, or order the doors to be unlocked if the keys have been locked inside.
The key to these capabilities is a data bus - an electronic highway inside the vehicle that carries coded electronic messages for several systems along a common wire.
A data bus also is central to delivering engine diagnostics. But this bus has its genesis in the quest for less-polluting vehicles.
The advent of the second generation of on-board diagnostics, known as OBD-II, forced automakers to substantially increase the number and capabilities of sensors in the powertrain. These sensors monitor the performance of the engine, transmission and catalytic converter - tracking events such as engine misfires -to give early warning when emissions levels rise.
Data from the sensors flows along a data bus to the engine-control computer, which watches for problems and sets diagnostic trouble codes.
'It says that the automakers are looking at working with the basics, a cell phone, model and GPS, and add value using those features rather then going to a flow-blown system,' said Paul Hansen, editor of The Hansen Report on Automotive Electronics.
The use of telematics is not new.
Owners of heavy-duty truck fleets, such as J.B. Hunt or Yellow Freight, are able to keep constant tabs on their trucks' whereabouts. Each truck has a receiver/transmitter that provides the truck's location, engine data and load status. The device also sends messages to the driver.
Drury of Siemens noted that some heavy trucks do not have fuel gauges any more. The central dispatch office monitors fuel usage and tells the driver how much fuel to take on for the next run, minimizing weight and costs.
And the automakers have been using telematics for their own purposes, said Drury, who worked as an engineer with Ford before joining Siemens.
Engineers at vehicle engineering centers in Michigan use personal computers to call up information being transmitted from vehicles at test tracks around the nation, he said.
But there are hurdles, Drury notes.
The first is configuring the system to create a secure link between the engine control data and the receiver. For vehicle navigation systems, suppliers and automakers are working to develop a standardized 'gateway' to the data bus that would give a system access to the information it needs, without opening up the vehicle's entire electrical network to interference.
Such a gateway would likely be necessary for service, Drury said.
There is also the issue of invasion of privacy.
It would be important that people communicating with the vehicle would have an identification number, but not have access to personal information about the owner, Drury said.
And there is also the resistance of some service technicians to computerized repair equipment.
'Over the last decade,' says Drury, 'the automakers have put some high-tech tools for diagnosing vehicles into the shops, but getting technicians to use them is another thing.'
Dale Jewett is a Detroit-based Automotive News staff reporter.