ABS module or sensor failure on the 2009 Toyota Prius
3 crashes 3 of the 29 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.
When abs module or sensor failure gets reported
Owners of the 2009 Toyota Prius report ABS module or sensor failure at a median of 15,000 miles. A quarter of the reports come in before 1,200 miles and a quarter after 25,000 miles, from 22 reports that carried an odometer reading.
A part like this is normally expected to survive 95,000 miles. It is the 7th most-reported problem on this model year.
The mileage distribution
The reported range runs from 500 miles at the tenth percentile to 100,000 miles at the ninetieth, a spread of 97,400 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.
86% of the dated reports were filed under 36,000 miles.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| 500 miles | 1,200 miles | 12,500 miles | 23,000 miles | 97,900 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, 3 a crash is 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 $500–$2,400 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 13 model years of this car. It shows up earliest on the 2010, at a median of 5,000 miles, and latest on the 2013 at 190,000 miles.
By volume the 2010 carries the most reports, with 265; the 2009 has 29. 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.
Prius braking failure. I have experienced several instances (four or five) of a braking failure on my 2009, second generation toyota prius. It has occurred during relatively slow speed braking, such as approaching a stop sign, coincident with hitting a severe bump, such as a pot hole or crossing rough railroad tracks. There appears to be a surge where the brakes are ineffective for a short period of time---less than a second. I describe it as a surge but it may well be just a total release of the brakes. It seems to be most severe the greater the bump. I have only experienced this at speeds less than 30 MPH or so. There has been no loss of control of the vehicle. Normal braking returns immediately. I have owned the vehicle since november, 2008. This problem was reported to my dealer who suggested that it was normal anti-lock braking action and expressed little interest in trying to determine the cause. I've been driving for over 50 years and at least 10 years with anti-lock brakes and have never felt this type of action from any other vehicle. *tr
In march 2009, we purchased a toyota prius at the toyota of northwest arkansas toyota dealership of rogers, ar. On july 29, 2009, I pulled up to the curb to park at a strip mall. Upon applying the brake, the car lunged forward. I turned right on the sidewalk and the right side of the car ran into a post/upright that holds up the roof over the sidewalk, damaging the right side of the car (both doors, etc) and the post/upright. The cost to repair the car and the post/upright was approximately $5,300. There were no personal injuries (thank heavens no one was on the sidewalk). The police were called and the policeman said it was a non-reportable accident since it did not occur on a street and no personal injuries were involved. We saw press releases concerning floor mat problems and removed the floor mat. We also stopped at the dealership to inquire if there was something more we should do and were given a telephone number to call. The person we spoke with assured us that the problems did not pertain to the 2009 car we have. However, with the washington post saying "toyota said it had corrected problems with the antilock brake system…
2009 prius - I've had what felt like the car was recovering from a skid but there was no skid. During this time I sometimes see the skid warning light on and hear one wheel spinning fast. It occurs very rarely but when it does occur the road is wet or bumpy. An easy way to see this problem is to drive down the fdr north of the triboro bridge. If you want a test track of bumps this is it. It has occurred randomly since I got the car. A friend with a 2004 prius reports the same problem. I guess we just thought it was something the prius did. I haven't thought of it as a safety problem. *jb *tr
Also reported on the 2009 Toyota Prius
Other brake problem
Headlight failure or clouding
Other speed control problem
Other lighting problem
Other electrical problem
Loss of braking
How far this goes
Complaints are voluntary, so 29 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 abs module or sensor failure happen on the 2009 Toyota Prius?
Across 22 owner reports that included an odometer reading, half were filed by 15,000 miles. A quarter were filed before 1,200 miles and a quarter after 25,000 miles. These are the mileages owners reported when they complained, not a prediction for any individual car.
How common is abs module or sensor failure on the 2009 Toyota Prius?
29 reports have been filed with NHTSA, about 0.3 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