Unclassified problem on the 2012 Hyundai Sonata
13 crashes 7 fires 6 injuries 1 death 27 of the 189 reports for this failure mention a crash, a fire, an injury or a death. Those are the owner's words on the complaint form, not a verified finding, and one report can mention more than one.
Only 94 reports for this mode came with an odometer reading, which is too few for percentiles to mean anything. The page is here because someone linked to it; treat the figures as anecdotes, and see the full report for this year instead.
When unclassified problem gets reported
Owners of the 2012 Hyundai Sonata report unclassified problem at a median of 77,500 miles. A quarter of the reports come in before 57,500 miles and a quarter after 110,000 miles, from 94 reports that carried an odometer reading.
It is the 80th most-reported problem on this model year.
The mileage distribution
The reported range runs from 12,500 miles at the tenth percentile to 140,000 miles at the ninetieth, a spread of 126,118 miles across the middle 80% of reports.
A spread this wide points at use rather than design. Towing, climate, service history and city mileage all move a failure like this, so the median is a weak guide to any individual car.
16% of the dated reports were filed under 36,000 miles.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| 12,982 miles | 57,047 miles | 76,500 miles | 110,436 miles | 139,100 miles |
Read the 10th percentile as “one report in ten arrived this early”. Exact figures are shown in this table because it is the table of record; everywhere else on the site they are rounded to the precision the sample can carry.
What a percentile can and cannot tell you here
These five numbers describe the readings owners gave, in order. The median is the middle one: half the reports arrived below it. The 10th and 90th are the edges of the bulk of the distribution, and the distance between them is the part worth reading. A tight spread — say 70,000 to 95,000 miles — points at something that wears out on a schedule, and the schedule is knowable. A wide one, 20,000 to 190,000, points at a fault that hits some cars and never troubles others, which means the mileage on the listing in front of you tells you very little about your odds.
What these figures are not is a survival curve. Every reading here comes from a car whose owner filed a complaint, so the sample contains only failures: it cannot say what share of the fleet made it past 150,000 miles untouched, because those owners had nothing to report. Nor is the mileage the moment of failure — it is the odometer reading as recalled at the time of filing, which may be weeks later and is sometimes rounded to the nearest ten thousand by the person typing it.
Percentiles are shown at all only once 8 readings exist for the vehicle and mode. Below that the middle of a handful of numbers is noise wearing a decimal point, so the figures are withheld rather than dressed up.
What happens, and what it costs
Of these reports, 13 a crash, 7 a fire, 6 an injury and 1 a fatality are mentioned. Owners write their own complaints and the agency does not verify them, so read this as what the reports say happened rather than as a confirmed count.
The same failure on other years
The same failure is reported on 24 model years of this car. It shows up earliest on the 2023, at a median of 100 miles, and latest on the 2001 at 120,000 miles.
By volume the 2011 carries the most reports, with 333; the 2012 has 189. A mode that appears across most years of a model is usually a design choice rather than a bad batch.
If one year stands out to the left, that is the year to avoid; if the whole line sits at a similar mileage, this is wear rather than a defect in one production run.
Tick median reported mileage Solid middle half of reports Faint 10th to 90th percentile Colour how bad the failure is when it happens
What owners wrote
Verbatim from NHTSA complaint narratives, trimmed for length. The mileage is the one the owner gave.
Vehicle was parked in parking lot when we came out the driver side curtain air bag (front and back) had deployed....inspected for damage in parking lot and there was none found in other words nobody hit vehicle....took vehicle to dealer in columbia missouri, joe machens hyundai, and they indicated they had never seen anything like this and were contacting hyundai usa for information...they ran computer codes on vehicle everything was fine...also checked for damage to vehicle and none found...major concern is that if this happened while driving this could have been a serious problem...could this be a major a problem with 2012 sonatas?? *tr
I was in my parking space and had to put the car in reverse to get out of the space. With my foot on the brake and the car in reverse, it took off at an incredible speed, did a semi-circle, and hit another car. I brought the car to my local hyundai dealer who was unwilling to do anything about the event or check out the car. I plan on contacting hyundai corporate to provide them with this information.
I was getting ready for work and the temperature outside was -2 degrees so I went to warm up the car for 20 mins and then started to head out to work. As I was leaving not even 5 mins later I started to smell something burning. So I pulled over and started to see smoke, then I started to look around to find out where it was coming from and I see smoke coming from the bottom of the back seat right behind the driver seat. So I started taking my personal belongings out of the vehicle. After removing my personal belongings, I went to the car and now there was more smoke coming from the bottom of the rear seat closest to the rear door driver side. So then I pulled up the seat and I see flames, and there were flames, I call 911 and they came like in 5 mins.I'm just blessed that I didn't have my kids with me. *tr
Also reported on the 2012 Hyundai Sonata
Other engine problem
Other steering problem
Other electrical problem
Airbag warning light or occupant sensor fault
Steering column or shaft failure
Other brake problem
How far this goes
This page is kept out of search results because 189 reports is not enough to publish percentiles from. It stays reachable because somebody looking at this exact car would rather see the reports than be told there are none.
Complaints are voluntary, so 189 is a floor and not a count of affected cars. Mileages are typed in by owners and cluster on round numbers. And the mode itself is assigned by software reading the complaint text, which is reliable in bulk and fallible one report at a time.
Questions this page answers
At what mileage does unclassified problem happen on the 2012 Hyundai Sonata?
Across 94 owner reports that included an odometer reading, half were filed by 77,500 miles. A quarter were filed before 57,500 miles and a quarter after 110,000 miles. These are the mileages owners reported when they complained, not a prediction for any individual car.
How common is unclassified problem on the 2012 Hyundai Sonata?
189 reports have been filed with NHTSA, about 0.8 per 1,000 vehicles. Complaints are voluntary, so this is a floor rather than a count of affected cars.
What this is and is not. These are the mileages at which owners chose to complain to a federal agency, which is not the same as the mileage at which the part fails on every car. It skews toward failures that happened outside warranty, cost real money, or frightened someone. It is still the only public dataset that carries failure mileage at all, and the shape of a few hundred readings is informative even when a single one is not. Methodology · JSON · this failure on other cars
Source Owner complaints and recall records published by the US National Highway Traffic Safety Administration, model years 1996–2027 Figures rebuilt Published by AtWhatMileage How every figure is computed