As electric vehicles become more common in workshops, many technicians still approach them with the mindset they’ve developed from working on petrol or diesel cars. But EVs are different; from regenerative braking systems to high-voltage components, they require a new skill set, different tools, and a deeper understanding of electrical diagnostics.
You can’t just unplug an EV and plug it back in like it’s a dodgy printer, unless you fancy jumpstarting your eyebrows.
This blog breaks down the most common mistakes technicians make when working on electric vehicles and how to avoid them.
Before You Start, Learn
Why Electric Vehicles Demand a Different Mindset
Working on an electric vehicle isn’t just “same job, new powertrain.” It’s a full shift in how you approach diagnostics, safety, and repairs. You need to understand high-voltage systems, new braking behaviours, and brand-specific service platforms; otherwise, even routine jobs can go sideways.
Mistake-1: Treating All Electric Vehicles the Same
Not all electric vehicles are built alike. Service modes, software platforms, and diagnostics can vary widely from brand to brand, and so do the risks.
Take Tesla, for example. It uses a unique service environment with app-based workflows and a distinct user interface. Compare that with more conventional OEMs, and you’ll quickly see how a one-size-fits-all approach leads to confusion or, worse, mistakes.
Refer to our Tesla foundation course for more information.
This course introduces essential Tesla systems like Toolbox and Loki, helping technicians understand Tesla’s electric vehicle architecture and what sets it apart.
Mistake-2: Overlooking the Regenerative Braking System
In many EVs, the regenerative braking system does most of the stopping in everyday driving, which means technicians might misinterpret wear on mechanical components. Brake pads may last longer, but when failure occurs, it can be sudden.
Misdiagnosis also arises from failing to understand how regen interacts with hydraulic braking. In hybrids and EVs, both systems work together, and failing to test one without considering the other leads to incomplete servicing.
Learn more about Braking Systems in Hybrid & Electric Vehicles. Here we explain how the regenerative braking system works, how it affects brake wear, and how to correctly diagnose faults in both hydraulic and regenerative systems.
Mistake-3: Misdiagnosing High-Voltage Drive Systems
The drivetrain in an electric vehicle is nothing like that of an ICE vehicle. It’s all about inverters, electric motors, and high-voltage power control units. Misreading fault codes, replacing unnecessary parts, or even failing to isolate faults correctly are all-too-common mistakes.
Our Electric Drive Systems course covers diagnostic approaches specific to electric vehicles, including how to work with inverters, converters, and single-speed gearboxes.
Mistake-4: Mishandling the High-Voltage Battery of EV
The battery of EV is one of its most expensive components and also the most dangerous to service without training. From thermal events to current leakage, even experienced technicians make errors due to a lack of hands-on knowledge.
Understanding internal structures, such as modules, cells, BMS (Battery Management System), and cooling systems, is key to both safety and effective fault diagnosis. In our High-Voltage Battery (REESS) course, the training focuses on the structure, chemistry, and safety protocols for servicing EV batteries. It also teaches technicians how to safely disassemble and inspect components, and how to recognise signs of serious internal issues.
Mistake-5: Thinking Level 2 Skills Are “Good Enough” for Repairs
Entry-level EV qualifications are often focused on safe working practices — but not necessarily on actual electric vehicle repairs. That’s a major problem in workshops where high-voltage repairs are mistakenly assigned to underqualified staff.
Without Level 3 training, you’re not legally or technically prepared to perform high-voltage component replacements or diagnostics — and that creates serious liability.
Our IMI Level 2–3 Electric & Hybrid Vehicle System Repair & Replacement course clarifies the difference between general awareness (L2) and advanced repair work (L3). Emphasises proper safety isolation, fault tracing, and component replacement within electric vehicles.
Mistake-6: Skipping Brand-Specific or System-Specific Training
From Tesla to Nissan, different EV brands come with unique service procedures, tool access requirements, and diagnostics. Even if you’ve trained on one platform, working on another may demand a completely different approach.
For example, Nissan’s Leaf uses a different battery management interface and control logic than a Tesla Model 3. Without the right knowledge, even basic procedures can go wrong.
At ATA you can take our Tesla Foundation Training, it is an excellent example of why general EV training isn’t enough. Tesla’s Toolbox, remote diagnostics, and vehicle app integrations require targeted training.
Stay Ahead… or Get Zapped Trying
Working on electric vehicles without the right knowledge is like playing darts in the dark, you might hit the target, or you might take out a fuse box and your dignity in one go.
Think you can wing it with EVs?
That’s a bold strategy… until you’re staring down a 400V battery and Googling “what’s that humming noise?”
There’s no room for guesswork when high-voltage systems, regen braking, and software quirks are in play. If you’re serious about avoiding singed eyebrows and building a workshop that’s future-ready, the answer is simple: get trained, get confident, and stop treating every EV like it’s just a fancy toaster on wheels.
With the right EV courses, you won’t just keep up — you’ll lead the charge.