Technology discourages backyard mechanics

Try standing on a busy street corner during rush hour traffic. Watch the hundreds of cars and trucks that speed by in synchronization with four-way traffic lights that also allow for pedestrian crosswalk flow. Locate your geographical position on your cell phone “map app” and then zoom out to see all the surrounding streets and intersections, first in Las Vegas and then in Clark County. If you can zoom out to the point where you can see about 5 million of these street intersections working together, you’ll get an idea of what the inside of a car’s electronic control unit, or ECU, might look like.

The automotive industry did not start adapting microcontrollers into cars until the 1980s. Up until that time, a backyard mechanic could perform a tune-up on his own car by changing just the mechanical components with a little help from a voltmeter and dwell meter. After replacing the spark plugs, distributor cap, rotor, points, condenser, air filters, fuel filters and PCV valve, the mechanic could use a dwell meter to set the dwell angle and timing. Adjusting the carburetor needle valves with a screwdriver could also fine tune the air-fuel mixture.

In response to the Clean Air Act of 1981, General Motors Corp. started introducing electronically controlled fuel injection systems into its Cadillac, Pontiac and Corvette lines. Delco Electronics, a subsidiary of GM, soon became the largest manufacturer in the world for these electronic control systems.

An Engine Control Unit originally consisted of a small eight-bit microprocessor, some memory space, and an input-output interface. On the input side, the ECU monitored sensors throughout the automobile that fed the ECU data about temperature, pressure, air flow, vibration, crankshaft position and other changing variables. Based on this data, the ECU computed and output the best settings for actuators that controlled fuel injection, idle speed, ignition timing and other components in the fuel injection system. Input and output functions of the ECU have been extended over the years to also govern automatic transmission shifting, anti-skid braking, anti-theft systems and automatic cruise control. Mechanical systems have now given way to mechatronic systems.

Today’s automotive technicians must be just as skilled in electronics systems troubleshooting as they are in mechanical systems troubleshooting. In addition to the traditional tool box filled with wrenches, screwdrivers and drills, they will also need to add a laptop computer, an electronic systems scanner, a throttle switch simulator and breakout boxes in order to test and tune the electronic control systems on modern vehicles. Many times a problem can be traced to a defective sensor or wiring connection rather than a defective component subsystem, even though initial error messages may point in that direction.

To find out more about the training available to new automotive technicians that will help them cope with today’s automotive problems, I talked with Paul Pate, director of the Transportation Technology Program at the College of Southern Nevada. It was comforting to hear him paint an optimistic picture about the ongoing training programs at the college. He said that, although these systems are complex, the automotive industry has been using them for years. Much of today’s technologies have been tested and proven over time.

The college’s Cheyenne campus in North Las Vegas now offers classes that cover all phases of automotive electronics, from basic electricity fundamentals to hybrid technology systems. A new advanced class, called “Hybrid Vehicle Service Techniques,” specifically teaches how to troubleshoot and repair hybrid vehicle platforms, once a student has mastered both electronic and internal combustion engine technology classes.

In addition, an automotive engineer from General Motors Corp., who has worked on the Chevrolet Volt program, recently spent a week at the College of Southern Nevada training the transportation department’s staff about automotive industry flexible fuel technologies. A new class called “Introduction to Alternative Fuels” was launched this year and includes a hands-on lab where students learn to make hydrogen from water and sunlight to power a small fuel cell in a model car.

So, rest assured. You might not know how to work on your car nowadays, but rest assured a well-qualified mechanic does.

Stan Hanel has worked in the electronics industry for more than 30 years and is a long-time member of the Electric Auto Association and the Las Vegas Electric Vehicle Association. Hanel writes and edits for EAA’s “Current Events” and LVEVA’s “Watts Happening” newletters. Contact him at stanhanel@aol.com.