Take the engine out of a car and you take out the single largest source of complaints in the federal file. So what do electric vehicle owners complain about instead? DefectFile's register holds 22,136 distinct federal complaints against battery-electric vehicles across 1,023 model-year entries, from the earliest Nissan Leaf to the newest Rivian, and setting their complaint profile against the whole fleet's 2.15 million records produces one of the clearest before-and-after pictures in the file. The engine vanishes, as expected. What replaces it is not the battery. It is the software that drives.
What disappears
Fleet-wide, engine complaints are the largest family in the file at 13.4 percent of all complaint records. On EVs they are 2 percent, mostly loose usage of the category for propulsion issues. Powertrain complaints run at less than half their fleet share, fuel-system complaints likewise, and the pattern is exactly what removing pistons, oil, gaskets, injectors, and a multi-speed transmission should produce. Whatever else is true of electric cars, the complaint file confirms the core mechanical promise: the failure-prone heart of the twentieth-century car is genuinely gone.
What replaces it: the driving software
Driver-assistance complaints, the ADAS family, covering systems like automatic emergency braking, lane keeping, and full self-driving features, make up 25 percent of the EV complaint file. Across the whole fleet, that family is 2.1 percent. That is a twelvefold overrepresentation, and it makes driver assistance, not batteries, not charging, the number one thing electric vehicle owners formally complain to the government about.
Two honest qualifications belong next to that number. First, the EV file is Tesla-heavy: about six in ten EV complaints on record concern a Tesla, the ADAS complaints concentrate there, and Tesla's driver-assistance stack is, as covered in our tour of the open docket, currently the subject of five open federal investigations. Second, EVs are young, modern vehicles being compared against a fleet file that reaches back to 1981; older cars generate no ADAS complaints because they have no ADAS. The overrepresentation is real, but it is partly the story of when EVs were built, not only of what they are. The severity fields owners file with these complaints, which under our methodology stay attached to the family as a whole, are not small: the EV ADAS family carries 1,218 crash reports and 117 death reports as filed, unverified, by complainants.
The rest of the new profile
Electrical-system complaints run at 18.1 percent of the EV file against 11.5 fleet-wide: charging equipment, onboard chargers, 12-volt systems that strand a car with a full battery, and the screens that control everything. This is where the battery-adjacent grievances actually live, and it connects to the repair programs in our warranty extension guide: the Hyundai Ioniq 5, whose charging control unit failures made it the most complained-about non-Tesla EV in the file at 1,323 complaints, now carries a 15-year, 180,000-mile warranty on exactly that component. Speed-control complaints, largely perceived unintended acceleration, run half again above fleet share. Suspension runs slightly above, consistent with vehicles that weigh more than their gas equivalents.
And then the surprises in the other direction. Brake complaints, which folklore says regenerative braking should multiply, run below fleet share: 6.2 percent against 8.9. Steering runs below. Airbag complaints run at a third of fleet share, though that one deserves its asterisk: the fleet's airbag total is swollen by the Takata era, which most EVs simply postdate. The one category built specifically for electric propulsion, the hybrid and EV systems family, barely registers at all, because the agency's component taxonomy predates the technology; electric-car problems get filed under the old headings, which is why reading the EV file requires exactly this kind of translation.
The league table
The most complained-about electric vehicle in the file is the 2023 Tesla Model Y, with 1,139 distinct complaints, followed by the 2021 Model Y and the 2018 Model 3, the first mass-production year. The 2021 Model Y also holds the EV recall record at 23 campaigns, though many are the over-the-air software recalls covered in our largest-recalls piece, a genuinely new kind of entry in the register. By nameplate, the Model 3 leads with 4,274 complaints, then the Model Y at 4,076 and Model S at 3,384; the top non-Teslas are the Hyundai Ioniq 5, the Nissan Leaf, whose 1,090 complaints across fifteen years of service is a quietly good record for the segment's oldest vehicle, the Volkswagen ID.4 at 991, whose 2023 model year is the most complained-about non-Tesla EV year on file, and the Chevrolet Bolt EV at 970, most of them the battery fire saga that produced its park-outside recall.
What it means if you are shopping
The file's advice to an EV shopper is specific: the electric test drive is a software test. The mechanical systems that dominate a used gas car inspection, engine, transmission, fuel delivery, barely register here. What owners actually report is driver assistance behaving unexpectedly, charging and electrical faults, and acceleration events. So exercise the driver-assistance features on the test drive, in conditions like the ones you drive in; verify charging on the connector types you will use; and read the vehicle's page, where every complaint family above, plus the recalls and any open investigation, is already laid out for the specific year you are considering.