Hybrid & Electric Vehicle Corner
Hybrid and Electric Vehicle Student Success Stories
by: Curt Ward (Professor at Joliet Junior College)
As I write this article, the fall semester is almost complete and finals week; and the winter holidays are nearly upon us. Most months when I sit down to write this article, I highlight some hybrid or electric component or system that we have researched, and I share the findings and how you might implement the information in your classes. This month I am going to do something different. Instead, I am going to share some of our student successes related to hybrid and electric vehicle repair. My hope is that these successes will inspire you to do something similar with your students.
For those of you who are not familiar with the automotive program at Joliet Junior College, our students participate in a live customer shop class one-day-a-week during each of the four semesters they are enrolled in the automotive program. The students who complete the hybrid and electric vehicle class get the opportunity to work on customers vehicles with this technology when they are scheduled. What follows is a small sample of the repairs our students have completed during the last year.
The first vehicle is a third generation 2015 Toyota Prius with over 150,000 miles on the odometer. The customer concern was that the malfunction indicator lamp (MIL) was illuminated, but there were no driveability concerns. The student confirmed the concern and found a current code in the engine controller of P261B. This code is a “Coolant Pump B Control Circuit” issue. The coolant pump is electronically controlled by the powertrain control module (PCM). The student followed the diagnostic procedure and determined the coolant pump was not spinning at the speed that was commanded by the PCM. The coolant pump was removed and found to be physically binding as it turned (See Figure 1 – Coolant pump). The student replaced the pump, refilled the cooling system, performed the cooling system bleed procedure and verified the repair.
The second vehicle is a 2014 Toyota Camry Hybrid with over 200,000 miles on the odometer. The vehicle was towed to the shop in a no-start condition and the malfunction indicator lamp (MIL) was illuminated. A review of the hybrid controller revealed three codes, P0A0F engine failed to start, P0A7F hybrid battery pack deterioration, and P0A80 replace battery pack. The data stored in the freeze frame for code P0A0F indicated low voltage in battery blocks 4 and 12 (See Figure 2 – Freeze Frame). The battery was removed from the vehicle and opened for further diagnosis. Inspection revealed that pet hair had been drawn into the battery by the cooling fan and the restriction was creating a battery overheating concern that resulted in the deterioration of the cells (See Figure 3 – Battery). The battery was replaced, the cooling system was cleaned, and an aftermarket filter was installed at the air inlet to prevent further intrusion of pet hair into the system.
The third vehicle is a 2012 Chevrolet Volt. The vehicle came into the shop with a message in the information center to “Service High Voltage Charging System” and the high-voltage battery would not wall charge. A visual inspection revealed the level in the battery coolant reservoir was low. This condition will prevent the vehicle battery from charging via the cord. The students performed the cooling system pressure test and inspected the high-voltage battery for the presence of coolant per the GM technical bulletin (See Figure 4- Coolant inspection). The system held pressure, and the paper towel remained dry which indicated no coolant had entered the high-voltage battery. The coolant reservoir was topped off and the battery charging system was verified to be working normally. A subsequent conversation with the customer revealed the cooling system had been serviced elsewhere recently and trapped air was likely the cause of the low coolant level.
The last vehicle is also a Chevrolet Volt. The vehicle was driven into the shop with malfunction indicator lamp (MIL) illuminated. A scan of the 
modules showed two codes for loss of isolation, one in the battery, and one in the battery charging system (See Figure 5 – Scan Data). A series of isolation tests with the megohm meter did not indicate any problems with either system. Further investigation revealed a software update that needed to be performed to address these fault codes. Using the GM MDI and our subscription we were able to successfully update the software, eliminate the codes, and verify that all systems were working properly.
I believe the ability to work on live vehicles after successfully completing the classroom and lab activities is the component that makes our graduates more successful when they leave the program and enter the workplace. None of the repairs were difficult, however, they all required a thorough understanding of how the system operated and a complete diagnosis. I understand that not all programs are equipped, or allowed, to bring live work into the learning environment, but I do believe that the more we can expose our students to “real world” scenarios, the more successful they will be when they graduate.
I will finish this article with the same offer I make after each of my presentations. If you are interested in getting started in the process of adding hybrid and electric vehicles to your curriculum or want more information, please feel free to reach out. I am more than willing to sit down in-person or online and share my experiences. Are you looking for a classroom textbook? Reach out to Pearson and ask for a review copy of the all-new Electric and Hybrid Electric Vehicle text that Jim Halderman and I co-authored. It is a comprehensive text covering all the latest information on the subject.