The title of the seminar was “Your New Transmission Business: How To Properly Perform Comprehensive Hybrid And Electric Vehicle Motor-Generator Testing.” What a mouthful, and appropriate to the amount of information Dr. Mark Quarto of Automotive Research and Design packed into this 90-minute presentation.
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“Only two hybrid models were offered in the market in 2002,” Quarto told ASRW attendees. “Today, there are 57 models offered by various manufacturers and the number is growing exponentially. The number of hybrids will double, maybe even triple over the next three to five years.” Quarto further explains that increasingly demanding CAFE and emissions requirements is driving the technology. And he should know.
Quarto began his career in the automotive industry as a technician, both in dealerships and aftermarket shops. He joined GM and earned a doctorate in technical education, serving in a variety of roles during his tenure there, including a role as engineer and manager in the Advanced Powertrain Technology Systems group. He also was involved in the development of diagnostic systems and service solutions for the Chevy Volt and other GM hybrid and alternative energy projects. He retired in August 2012 to join AR&D as its chief technology officer, responsible for the design and development of diagnostic test equipment and technical education related to hybrid and electric vehicle (EV) propulsion and energy management systems.
“There is an increasing market for hybrid repair,” says Quarto. He further explained to his audience that many hybrids are out of factory warranty, and shared several other revenue-generating sources shop owners could tap into, specifically when assessing problems with the hybrid electric drive motor-generators. The key, he said, is to understand the pros and cons of the various testing methods available and how they apply to different lines. He referenced an OEM study that investigated a variety of testing methods, looking for a standard procedure and tooling that could easily be applied to any platform.
Problems in the electric motor-generators can range from total loss of propulsion to torque imbalance, or shudder. Often these faults can mimic engine problems that can lead a tech down the wrong diagnostic path. In addition, because of the failure thresholds programmed into the control module’s software, faults can exist and not record a diagnostic trouble code (DTC).
Quarto went on to show attendees an overview of the different propulsion systems in the market place. He reviewed the most common, conventional testing methods in use in the field, including insulation testing, resistance testing, voltage and current testing. He stressed that these methods only test a part of the overall system, and may not apply to all makes and models.
He then moved on to discuss more advanced testing methods: electric signature analysis, voltage/current using a scope and motor circuit analysis. The latter, says Quarto, is able to test for several possible problems (cable failure, connection faults, shorts between coils, for example) and can be done with the unit in or out of the car. Imagine being able to test the motor-generators without actually running the vehicle. How about verifying the integrity of a used unit for local salvage operations?
Based on the results of the OEM research referenced earlier, Quarto wound up his presentation with a demonstration of the All Test Pro AT33EV tester. This product performs a motor circuit analysis and is also capable of testing the condition of the rotor without having to rotate the rotor assembly. He pointed out that the tool is self-powered, and performs only low-voltage (under 10 volts) tests. Of all the methods analyzed in the study, this tool was ranked as the best overall performer and the easiest to use by techs, even those with limited or no knowledge of hybrid systems.
If you missed his presentation yesterday, be sure to attend his 1 p.m. presentation today on the growing opportunities for hybrid battery pack service.
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