By Mike Davey
Hamilton, Ontario — August 8, 2017 — There’s nothing particularly difficult or unusual about the repairs to most hybrids and electric vehicles (EVs). The body panels and structure are no more or less exotic than any other car. However, they do present critical safety issues that simply aren’t present with conventional vehicles.
Mark Hodgins is an I-CAR instructor with 15 years of experience. In Canada, he’s become the go-to teacher for the I-CAR courses on electric hybrid safety.
“I’m very familiar with them, as I’ve been teaching the course for about nine years now,” Hodgins says. “Really, what’s essential is that you know how to approach it.”
Hodgins mentions that when he first started teaching the course, the majority of I-CAR instructors had little experience with EVs. He had even less experience than that, though. Paradoxically, this is why he decided to take it on.
“I thought it would be a perfect fit,” he says. “Since I didn’t know anything, if I could learn it, then I could definitely pass the knowledge on.”
The I-CAR training or its equivalent is absolutely essential for anyone who needs to work on these vehicles. As Hodgins points out, most techs have very little experience with electrical systems, but the I-CAR courses (ALT 01, ALT 02 and ALT 03) provide a good grounding in keeping team members safe.
“The first concern is that you’ve got to make sure the hybrid or EV is powered down,” says Hodgins. “Get permission from the owner to open the glove box and read the manual. After you’ve done that, contact the dealer and get the latest information. There might be an updated method and you want to make sure you’re doing it correctly.”
Once the vehicle is powered down, the most important thing to do is to figure out if there are any fault codes. In part, this is because faults may leave a charge somewhere in the system.
“Always assume the vehicle is energized, even if you’ve powered it down,” says Hodgins. “Don’t pull on bare metal, and always wear the right equipment.”
At minimum, the right equipment includes goggles, a robe and linesman’s gloves. These are heavy, insulated gloves used for working on electrically charged cables or devices. Hodgins notes that these be kept separate from other gloves and clearly labeled.
“You don’t want to use them if someone has been using them to haul scrap metal or something. Even a small tear means electricity can get inside,” he says.
It’s also important to indicate to the rest of the shop that the vehicle is a hybrid or EV. The I-CAR recommendation is to place a cone on the vehicle’s roof. This will help to prevent an unsuspecting technician from placing a hand on bare metal and receiving a serious electric shock.
It should be pretty obvious that these vehicles can carry a serious charge. What’s not obvious is just where the danger can be lurking.
“If it’s got an automatic start, disconnect the 12-volt battery and store the key fob,” says Hodgins. “You’ll also need to always have the drive wheels up on casters. This is because the drive wheels essentially act like generators. When you’ve got a damaged system, they could end up pushing power into some part of the system where there’s a short circuit.”
The first-generation hybrids and EVs used the big batteries just for propulsion and the 12-volt battery for almost all other functions. This worked, but it also drained the 12-volt very quickly.
“The solution for a lot of manufacturers was to tie some of those systems into the big batteries,” says Hodgins. “It works great, but now if you’ve got a 300-volt vehicle, you’ve also got a 300-volt air conditioning system! Other systems are often tied into it as well, like the power steering. You’ll see high-voltage cables running to these systems. That’s something else to be aware of.”
Most hybrids and EVs are now equipped with inertia switches that disconnect the power system on impact. However, there’s still an inverter/converter in the wiring harness. If you’re moving the vehicle, you may be charging the inverter/converter. This can also lead to a serious electric shock if you’re not careful.
Hodgins also points out that some batteries need extra caution when it comes to time in the booth.
“With nickel-hydride batteries, they can’t take more than about 160 degrees,” says Hodgins. “Make sure you keep the booth under that temperature, even when baking, or you may end up damaging the battery.”
Lithium-ion batteries aren’t affected by heat this way, but they’re less common.
Finally, Hodgins has one final piece of advice for techs who may be called on to work on hybrids or EVs.
“Take the courses,” says Hodgins. “Then you’ll have a good understanding of just what you’re up against.”
For more information, please visit i-car.ca.
