Unrepairable vehicles? It's certainly a thought that has crossed the minds of many technicians today. As the complexity of onboard electronics continues to escalate with each new model year, so does the frustration and anxiety associated with repairing these vehicles.
We've all seen "problem" cars that defy diagnosis and bounce from dealer to dealer and shop to shop. Everybody throws parts at it but nothing seems to make the problem go away. Because of the complex way that sensors and modules interact, identifying the root cause of a problem can be time-consuming and difficult. A minor glitch in one part of the system may affect another part of the system. To make matters worse, the engineers who design these systems don't always anticipate all the things that might go wrong. Consequently, the diagnostic trees in a manual may only lead you to a dead end.
Independent repair shop technicians who work on virtually any vehicle that drives in the door are at a distinct disadvantage on late model vehicles because they don't always have access to the same tools, service information and training as the dealership technicians. Even when they do have the latest scan tool and technical service bulletins, they may not be able solve a customer's problem.
Dealership technicians are also finding it more and more difficult to fix driveability and emissions problems. Sometimes the only "fix" available is to reflash the computer PROM with new programming in hopes it will make the problem go away.
Engineers Do Not Repair Cars, Technicians Do Not Design Cars
The core problem, as I see it, is a lack of information sharing between engineers and technicians. The OEM engineers who design electronics don't always share their detailed operating strategies with the technicians who have to troubleshoot and fix the electronics. Many of these same engineers are also totally out of touch with the realities of the repair business and give little or no thought to what it might take (or cost) to fix something when it breaks.
Including detailed descriptions of system inputs, outputs and operating strategies in service manuals would certainly make life easier for our readers. But it needs to be simplified and written by somebody who speaks the technician's language -- which usually isn't an engineer. Most of the gobbledygook these guys write is unintelligible.
Most technicians are educated enough to know how an oxygen sensor works, how the feedback fuel loop works, what OBD II codes are, how to read codes and scan tool data, and so on. But they may not be privy to the unique operating strategy or self-diagnostic logic that is used on a particular vehicle. Unless they have that vital information, they may not be able to track down and isolate the problem.
If you fully understand a system, you can usually figure out which scan tool data you need to examine, which sensors are involved in a particular function, and which circuits to check. Without this information, you're troubleshooting in the dark and often end up wasting a lot of valuable time chasing ghosts that don't exist.
Siemens VDO Electronics University
I attended an "Electronics University" seminar sponsored by Siemens VDO. One of the speakers was Jerry Rivard who is considered to be the "father of automotive electronics." Rivard began his career in aerospace engineering, which probably explains why electronics today seems so much like rocket science.
Rivard said it was an uphill battle to convince the auto makers electronics was the coming thing. What argument didn't accomplish, federal legislation did. Like it or not, the auto makers were forced to adopt computerized engine controls to meet fuel economy and emissions standards. But 25 years ago, nobody ever dreamed how far electronics would go. Today, up to 25 percent of a vehicle's price is electronic content.
In 1974, Rivard put together a list of "proposed" electronic systems that could be integrated into future vehicles. The list included many things we now take for granted: electronic cruise control, digital instrumentation, closed loop emission controls, antilock brakes, crash sensors and air bags, automatic door locks, electronic ignition and transmission controls. Many of the items that were proposed in 1974 didn't appear for almost a decade, and some have never been adopted (like an alcohol detection system that prevents drunk drivers from starting the engine). Other electronic options that are common today were totally unanticipated in 1974, things like traction control, vehicle stability control, electronic all-wheel drive, electronic valve timing, active suspensions, four-wheel steering, heads up displays, voice recognition, cellular telephones, backup warning radar systems, adaptive cruise controls, brake-by-wire, throttle-by-wire, night vision enhancement and hybrid electric vehicles.
Rivard said the history of electronics has gone though a series of phases. In the first phase (up to 1980), onboard electronics were fairly components like electronic ignition, electronic speed control and digital clocks. During Phase Two (1980 to 1990), things got a lot more complicated. We got computerized engine controls, oxygen sensors, feedback fuel controls, antilock brakes and more. In Phase Three (late 1980s up to about 2000), the separate electronic systems began to talk to each other. Engineers created engine, transmission, brake and body control modules that shared information and functions. OBD II onboard diagnostics was phased in from 1994 to 1996, which brings us to Phase Four where "systems engineering" is the buzzword.
The goal now is to tie everything together and to integrate electronics as much as possible into every aspect of vehicle control and operation. The Japanese and European luxury cars seem to be more advanced in this respect than their domestic counterparts, but all the OEMS are on the same track and headed in the same direction. All are adding more and more electronic content, more complexity and more cost to their vehicles.
All of this stuff we supposedly can't drive without is designed to enhance the driving experience and safety -- which it does as long as everything is working correctly. But when failures occur (which they inevitably do), it requires more and more time, thought and effort from the technicians who have to fix these systems.
Rivard says today's electronics are more reliable than ever before, but admits diagnosing and repairing increasingly complex systems is a serious issue. I wonder if diagnostics would be easier if the engineers and rocket scientists who design all this stuff were forced to spend a month out of every year fixing their creations?
The bottom line is this: To service today's vehicles, you can't fall behind the curve. You have to stay on the leading edge. That means keeping your tools and equipment up-to-date, getting all the training you can where ever you can find it, and making sure you have access to the latest electronic service information and technical service bulletins.