Overheating on the 2009 Hyundai Sonata
Only 2 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 overheating gets reported
There are 2 reports of overheating on the 2009 Hyundai Sonata, 2 with a mileage attached. That is too few to place the failure on the odometer with any confidence.
A part like this is normally expected to survive 102,000 miles. It is the 42nd most-reported problem on this model year.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| — | — | 80,200 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
Putting it right typically runs $400–$3,500 at an independent US shop. That range is an editorial estimate held in this site's failure-mode catalogue, not a figure from NHTSA, and it is a repair cost rather than a diagnosis cost.
The same failure on other years
The same failure is reported on 8 model years of this car. It shows up earliest on the 2015, at a median of 1,100 miles, and latest on the 2011 at 90,000 miles.
By volume the 2012 carries the most reports, with 21; the 2009 has 0. 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.
The car has had four rear caliper failures. These caliper failures have also consumed three sets of rear brake pads and two sets of rear rotors. The failure appears to be an excessive wear/slow to release condition that creates an overheating of the brake system, which has symptoms of a burning smell from the brakes and the rim of each wheel being far too hot to touch. Once we noticed the most recent failure, we noticed that the burning smell can start within about 1/2 mile drive.
My 2009 hyundai sonata with about 46k miles had brakes begin screeching with a metal-on-metal sound when braking. In fact, the sound continued when accelerating after completing a stop. On friday 12/26/14, the car repair shop replaced the pads and rotors. The next day, the brakes were quiet but overheated to such an extreme that there was a strong burning smell and the wheel could not be touched for fear of burning your hand. Returning to the car repair shop, one of the new rotors was completely black from the extreme heat. The pads, rotor, and calipers required completely replacing - even the new ones just purchased. This is a safety issue that hyundai needs to take responsibility for, issue recalls, and pay for my repairs. *tr
Also reported on the 2009 Hyundai Sonata
Other brake problem
Other body or interior problem
Other engine problem
Other electrical problem
Other driver assistance problem
Other powertrain problem
How far this goes
This page is kept out of search results because 2 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 2 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 overheating happen on the 2009 Hyundai Sonata?
Across 2 owner reports that included an odometer reading, half were filed by 80,000 miles. A quarter were filed before — and a quarter after —. These are the mileages owners reported when they complained, not a prediction for any individual car.
How common is overheating on the 2009 Hyundai Sonata?
2 reports have been filed with NHTSA, about 0.1 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