Other speed control problem on the 2009 Mercedes Benz C300
2 crashes 2 injuries 4 of the 5 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 5 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 other speed control problem gets reported
There are 5 reports of other speed control problem on the 2009 Mercedes Benz C300, 5 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 78,000 miles. It is the 26th most-reported problem on this model year.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| — | — | 35,660 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, 2 a crash and 2 an injury 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.
Putting it right typically runs $250–$2,000 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.
This mode is classified as critical, which means a failure can leave the car unable to stop, steer, or stay out of the way of traffic. It is weighted accordingly in the risk score.
The same failure on other years
The same failure is reported on 6 model years of this car. It shows up earliest on the 2016, at a median of 10,000 miles, and latest on the 2009 at 35,000 miles.
By volume the 2008 carries the most reports, with 7; the 2009 has 5. 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.
I was driving on the parkway at ~40 MPH and attempted to slow down by stepping on the brake. The car did not slow down but accelerated. And struck the car in front of me. Every time I pressed on the brake, the car accelerated so that the car struck the car in front twice. I tried to turn off the ignition and was unable to. Finally, I pushed hard on the brake enough to slow it down and I was ten able to put the car in neutral. The engine raced but I was then able to turn it off. Despite damage to the front of the vehicle, the airbags did not deploy. *tr
At 5:00pm, I was driving the mercedes benz c300, year 2009, 9010 miles in the parking lot of ymca in la canada, ca at 3 miles/hr. I prepared to stop the car and stepped on the brake, suddenly, the engine rev up and accelerated. The car jumped over the stop bumper but I pressed very hard on the brake and finally the car stopped and the engine was off. The front of the car was about 2 feet from the wall at the parking lot. I was so scared because it was the first time I experienced the unintended acceleration. I went to the gym and at 6:30pm I drove the car back home, it is about 6 miles from my house. I really feel unsafe with my almost brand new mb. I'll take off for work next monday and will take the car to the dealer for checking. I was lucky this time with no damage or injury because I was driving very slowly in the parking lot and ready to stop. However I don't want to take the chance next time, it's so dangerous, I can get kill or somebody can get hurt if my car jumps again. I do the research and see the complaint # 10330370 on 05/23/2010. The case was almost the same: when the driver stepped on the brake and the mb…
Tl* the contact owns a 2009 mercedes benz c300. The contact stated that while at the dealer he slowed the vehicle down in order to drive through an automatic door when sudden acceleration occurred causing the contact to crash into the door. The driver and two other people were injured. They were all taken to the hospital with injuries to the thigh, leg, and a bruised collar bone. The vehicle was destroyed. The insurance company was notified of the failure. A police report was filed. The manufacturer was notified and stated there was no acceleration failure or any related recalls. The contact stated the fly by wire caused the acceleration. The failure mileage was 35,660. Updated 02/07/13
Also reported on the 2009 Mercedes Benz C300
Airbag inflator rupture
No-start or intermittent start failure
Other electrical problem
Tail light, brake light or signal failure
Control arm, ball joint or bushing failure
Other steering problem
How far this goes
This page is kept out of search results because 5 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 5 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 other speed control problem happen on the 2009 Mercedes Benz C300?
Across 5 owner reports that included an odometer reading, half were filed by 35,000 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 other speed control problem on the 2009 Mercedes Benz C300?
5 reports have been filed with NHTSA, about 0.5 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