Technicians who repair today's vehicles have to deal with a variety of issues. First, there is the diagnosis. To figure out what is wrong with a vehicle, you first have to understand the technology that is inside it. You then have to apply current service information and use up-to-date tools to access the onboard electronics. Once you have determined the fault, you then have to fix it by installing the correct replacement part (and at a price your customer can afford). Nobody said it was easy to be in the auto repair business today.
The days of being able to fix most problems with seat-of-the-pants know-how and some basic tools is ancient history, unless, of course, you specialize in classic cars. But today's technician has to be able to work on virtually any vehicle that comes in the door. So here are some of the major issues they face.
ISSUE #1: KEEPING UP
OEM technology is changing at an ever-quickening pace. New engines, computers, fuel and ignition systems are being introduced every model year, and sometimes even during mid-year production. The rapid pace of change is being driven by two factors: government emissions legislation and competition between the vehicle manufacturers to provide more features and gadgets. Neither trend shows any signs of slowing down.
The next tier of low emission standards (Low Emission Vehicle II) will be phased in from model year 2004 to 2007, which will require even lower oxides of nitrogen (NOx) emissions than today's standards. The current rules allow up to 0.2 grams/mile of NOx. The new LEV II rules will cut NOx four-fold to only 0.05 grams/mile! What's more, diesel engines will also have to meet new NOx and particulate standards, which will require catalytic converters and EGR for the first time on big heavy-duty trucks.
Lower emissions requirements means tighter emissions controls under the hood and even more complexity than we have now. With each new generation of emissions compliance comes new diagnostic strategies, new diagnostic fault codes and new repair procedures. All this, of course, means today's technicians are in constant danger of falling behind unless they keep themselves educated and up-to-date. Though it typically takes up to three years for a new technology to filter down to the aftermarket, technicians can't afford to be three years behind the learning curve. Driveability problems can occur at any time after a new vehicle leaves the car dealer showroom floor. So you can't wait until a vehicle is out of warranty to learn how to diagnose and repair it. You have to be ready now.
Keeping up-to-date requires constant reading: trade journals, association publications, automotive consumer magazines, the latest technical service bulletins and diagnostic tips from your tool and equipment suppliers and parts suppliers. Quit reading and you quickly lose your edge.
Another valuable source of current information is the International Automotive Technician's Network. The iATN website provides numerous forums for discussing specific repair problems, sharing information and providing guidance. If you are not already a member, there are a lot of good reasons to join.
You should also take every advantage of technical seminars, clinics and training that are offered - and we are not just talking the freebies. To get top-quality training, you may have to actually spend some money and take some time off from work.
It is also important to get ASE certified if you are not already; and if you are, to keep your ASE certifications current. The ASE program provides a way to not only test your knowledge but to also assure your customers that you are competent to work on their vehicles.
Ongoing training is also essential. See the link below for a list of training resources and schools:
Automotive Technician Training ResourcesISSUE #2: OEM SERVICE INFORMATION
You can't work on today's cars without the latest service information. That includes service specifications, diagnostic procedures, repair procedures and OEM technical service bulletins. If you do not already subscribe to an OEM website, or an aftermarket database like that provided by ALLDATA or Mitchell 1, you are behind the times.
In recent years, the cost of printed service manuals has skyrocketed as vehicle manufacturers have tried to recoup some of their editing and printing costs. Manuals that used to sell for less than $20 now cost $100 or more! What's more, many vehicles now have multiple manuals to cover their various systems. Driveability diagnostics may be in a separate manual from engine/drivetrain/chassis. Climate control has become complex enough to usually warrant its own manual. There may also be a separate wiring diagram and electrical manual and another for the electronic transmission. Multiply all these manuals by the number of different makes and models of vehicles that are produced every year and you quickly realize how futile it is to even attempt to maintain a reference library of printed manuals.
Electronic databases are much more cost-efficient and compact. Updates come quarterly with the CD/DVD-based systems, and updates are even more timely with the online versions. But all this information doesn't come cheap. Cost is a major issue for many repair shops. Some vehicle manufacturers are making an effort to provide more free service information via the Internet, but others are realizing there is a buck to be made. The question is, how much will it cost? If it gets too expensive, the costs will have to be passed along to our customers who are already complaining about the high costs of auto repair.
Another issue that relates directly to service information is that of flash reprogramming computers in new vehicles. Today, it is a "dealer only" service. If a driveability or emissions problem is unfixable by conventional methods, the only cure may be to flash reprogram the vehicle's PCM using a scan tool and appropriate software. The aftermarket has been promised this technology (for a price), which will allow repair shops to download the latest "fix" directly from the OEM and load it into a customer's computer. But we are still waiting.
ISSUE #3: ACCESSING VEHICLE CODES
Since the appearance of OBD II in 1996, manual flash codes have become obsolete. Manual flash codes are still available on many older vehicles, but with each passing model year this population of vehicles is shrinking. Consequently, today's technician needs an OBD II-compliant scan tool or reader that allows him to access diagnostic information in the vehicle computer. Unfortunately, most pre-OBD II scan tools are not updatable because they lack the proper hardware to handle the various OBD II electronic protocols. And even when you buy a new OBD II-compliant scan tool, you still have to buy update cartridges or upgrade software every year thereafter to stay current. It is expensive but it is an unavoidable cost of doing business today.
Another question is which scan tool to buy? Many OEM scan tools have more built-in capabilities than their aftermarket equivalents. They can do certain test procedures or access data that may not be accessible with an aftermarket scan tool. But few shops can afford to buy a different OEM scan tool for every make they service. Spending $4,000 for a dedicated scan tool that only works on GM or Chrysler or Ford or Toyota or whatever vs. $1,500 for an aftermarket scan tool that works on a wide range of makes is a no-brainer for most shops. Even so, you still have to buy additional wiring harness adapters and software cartridges if you are going to work on imports as well as domestics.
Another issue is that some scan tools only provide the "generic" OBD II codes while others include many of the OEM "enhanced" codes (sometimes at extra cost). The enhanced codes for all the domestic and most of the Asian makes are usually available, but those for many of the European makes are not.
One approach some equipment suppliers have taken in an attempt to reduce diagnostic costs is to create software for a PC, laptop, Palm Pilot or Pocket PC that allows the device to function as a basic scan tool. If you already own one of these devices, you can convert it into an OBD II-compliant scan tool for a few hundred bucks.
ISSUE #4: OBD II
When OBD II came into being, it created a whole new approach to onboard diagnostics. Instead of being fault-driven (only setting a code after something failed), OBD II is emissions-driven and will set a code if it detects conditions that may cause emissions to exceed federal limits by 1.5 times. As a result, we are now seeing the Check Engine lights come on where there are no obvious driveability problems.
OBD II is so good at detecting conditions that can cause emissions to rise that the EPA now allows states to substitute a simple plug-in OBD II check for an I/M 240 or ASM loaded-dyno emissions test on 1996 and newer vehicles. Wisconsin was one of the first states to do this, and a growing number of other states now to OBD II tests on late model vehicles instead of a tailpipe smog check. The states like the OBD II test because it is cheaper, quicker and eliminates the risk of damaging a vehicle on a dyno. It also does a better job of identifying polluting vehicles than once-a-year tailpipe or dyno tests.
OBD II has the ability to detect ignition misfires, and will turn on the Check Engine light and set a misfire code when misfires exceed a certain limit. The OBD II system detects misfire on most vehicles by monitoring variations in the speed of the crankshaft through the crankshaft position sensor.
Misfire detection is a continuous monitor, meaning it is active anytime the engine is running. So too is the fuel system monitor that detects problems in fuel delivery and the air/fuel mixture. OBD II also has a "comprehensive monitor" that looks for gross faults in the sensors and engine control systems.
Other OBD II monitors are only active during certain times. The "non-continuous" monitors include the catalytic converter efficiency monitor, the evaporative system monitor that detects fuel vapor leaks in the fuel system, the EGR system monitors, the secondary air system monitor (if the vehicle has such a system), and the oxygen sensor monitors.
On some 2000 and newer vehicles, OBD II also has a thermostat monitor to keep an eye on the operation of this key component. The thermostat monitor will be required on all vehicles by 2002. On some 2002 model year vehicles, there is also a new PCV system monitor, which will be required on all vehicles by 2004.
The catalytic converter monitor keeps an eye on converter efficiency by comparing the outputs from the upstream and downstream oxygen sensors. If the converter is doing its job, there should be little unburned oxygen left in the exhaust as it exits the converter. This should cause the downstream O2 sensor to flatline at a relatively fixed voltage level near maximum output. If the downstream O2 sensor reading is fluctuating from high to low like the front sensor, it means the converter is not functioning.
The EVAP system monitor checks for fuel vapor leaks by performing either a pressure or vacuum test on the fuel system. For 1996 through 1999 vehicles, the federal standard allows leaks up to the equivalent of a hole .040" in diameter in a fuel vapor hose or filler cap. For 2000 and newer vehicles, the leakage rate has been reduced to the equivalent of a .020" diameter hole -- which is almost invisible to the naked eye but can be detected by the OBD II system. Finding these kinds of leaks can be very challenging. According to one expert, you can find a .040" leak with an ultrasonic leak detector but not a .020" leak. For such a tiny leak, you need a smoke or dye type of detector.
Something else technicians need to be familiar with are OBD II's "readiness flags" that indicate each monitor is doing its thing. As we said earlier, the misfire detection, fuel system and continuous system monitors are active and ready all the time, but the non-continuous monitors require a certain series of operating conditions before they will set, and you can't do a complete OBD II test unless all of the monitors are ready.
To set the converter monitor, for example, the vehicle may have to be driven a certain distance at a variety of different speeds. The requirements for the monitors can vary considerably from one vehicle manufacturer to another, so there is no "universal" drive cycle that will guarantee all the monitors will be set and ready.
As a general rule, doing some stop-and-go driving around town at speeds up to about 30 mph followed by five to seven minutes of 55 mph plus highway speed driving will usually set most or all of the monitors (the converter and EVAP system readiness monitors are the hardest ones to set). So if you are checking the OBD II system and find a particular monitor is not ready, it may be necessary to test drive the vehicle to set all the monitors.
The Environmental Protection Agency (EPA) realized this shortcoming in current generation OBD II systems, so it allows up to two readiness flags to not be set prior to taking an OBD II test on 1996 to 2000 vehicles, and one readiness flag not to be set on 2001 and newer vehicles.
ISSUE #5: PARTS ACCESSIBILITY
The main issue here is that automotive engineers do not fix cars for a living. Their focus is on designing parts and systems that can be manufactured as inexpensively as possible and assembled as quickly as possible. Serviceability is only an afterthought.
One reason why the OEMs went to 100,000-mile spark plugs was to improve long-term emissions reliability. But the other reason was to allow tighter packaging of underhood components. With less need to change the plugs, plug accessibility became a non-issue with the OEMs. Some vehicles with transverse-mounted V6 engines have almost no accessibility to the rear spark plugs. Unfortunately, this is not going to change.
It is the same story with many other components that may have to be serviced or replaced during a vehicle's life: air filters, fuel filters, oil filters, alternators, water pumps, EGR valves, A/C compressors, power steering pumps, fuel injectors, etc. The parts are buried and extremely difficult to replace. This increases the time and labor required to replace these items, which means higher repair bills for vehicle owners, who blame technicians for their high repair bills and not the engineers who designed the vehicles.
Even a low-tech job like changing a serpentine belt can be a nightmare on some applications. On Ford Windstar with a transverse 3.8L V6, the job is nearly impossible without a special tool to release the automatic belt tensioner.
Special tools are expensive, but the investment is well worth the time and frustration saved. Keeping your toolbox up to date is just as important as keeping your mind and electronic diagnostic equipment up to date.
ISSUE #6: LACK OF STANDARDIZATION IN SERVICE PARTS
Parts proliferation has been an ongoing problem for many years, and will continue to be an issue unless the OEMs realize the advantages of consolidating and standardizing many common service parts. Aftermarket parts suppliers have already realized this, and do a great job of consolidating where possible. But for many parts, little or no consolidation is possible because the replacement market is too limited. Some engines and parts are produced in such limited quantities that it is not profitable to reproduce these parts for the aftermarket. As a result, consumers have to pay dearly for "dealer only" parts when their vehicles need repair.
The Society of Automotive Engineers (SAE) should make more of an effort to standardize many common engine and drivetrain components. There is no technical reason why a single oil filter, a couple of air filter and battery sizes, maybe even a standard starter or alternator couldn't be used on a wide spectrum of makes and models. If engineers would make greater use of standardized off-the-shelf components and stop reinventing the same old components over and over every model year, the proliferation of parts would become a non-issue.
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