Control module (ECM/PCM/BCM) failure on the 2003 Toyota Corolla
1 crash 1 injury 2 of the 14 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 control module (ecm/pcm/bcm) failure gets reported
Owners of the 2003 Toyota Corolla report control module (ECM/PCM/BCM) failure at a median of 100,000 miles. A quarter of the reports come in before 80,000 miles and a quarter after 130,000 miles, from 11 reports that carried an odometer reading.
A part like this is normally expected to survive 92,000 miles. It is the 15th most-reported problem on this model year.
The mileage distribution
The reported range runs from 60,000 miles at the tenth percentile to 165,000 miles at the ninetieth, a spread of 102,168 miles across the middle 80% of reports.
When the reports scatter this far, the mileage is telling you about how these cars were driven more than about the part itself.
0% of the dated reports were filed under 36,000 miles.
The whole distribution
| 10th | 25th | Median | 75th | 90th |
|---|---|---|---|---|
| 60,832 miles | 80,000 miles | 98,000 miles | 128,999 miles | 163,000 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, 1 a crash and 1 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 $700–$3,000 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.
The same failure on other years
The same failure is reported on 12 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 2006 carries the most reports, with 87; the 2003 has 14. 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 bought my 2003 toyota corolla from a toyota dealership, took it home, and it began stinking like rotten eggs. I called the service department and they told me to buy more expensive gas that contains less sulfur. Four years of buying expensive gasoline, and I find out my catalytic converter has burned up and I need a new one for $1200. I found out that catalytic converters can be damaged if fuel is being mixed to richly, evident by a sulfur smell. I began researching this and found a toyota technical bulletin (http://www.autosafety.org/toyota%2003-04%20corolla%20catalyst.pdf) that states my specific model 2003 corolla had a manufacturers error all along. The ECM was set incorrectly to mix fuel too richly, and that if a customer complains of an excessive sulfur smell, the ECM and catalytic converter should have been changed under warranty! The catalytic converter failed while I was still under a 60,000miles warranty, however I was on vacation in california, and called a local toyota dealership service department, they told me my warranty did not cover the system, so I waited to get it fixed. The check engine light went off after…
Took my car into toyota dealer jim coleman toyota - because of the 2003 supplemental restraint system (SRS) electronic control module (ECM) safety recall notice that I received 2 weeks ago, made an appointment 2 days ago with the dealer for this recall - said to come in today at 2:00 pm for the repair. One hour and 45 minutes later - fix was not completed because they said that toyota corporation only allows for 12 sub-wire harness (filters) to be installed each day at each dealer through out the united states of america. They did not that the part and told me at the beginning of the service that they didn't have the part - but still needed to check my car to see if it needed to be repaired. They will have the part tomorrow and will fix tomorrow - hopefully. So my complaint is why does toyota not send the parts to the dealers to fix this safety recall and what will the NHTSA do about this problem with no parts from toyota to fix the problem - only 12 per day per dealer? Also I don't no if this is related but the passenger door lock doesn't work - when it rains it might or not work - problem occurred in 2005 and until this day…
Took my car into toyota dealer jim coleman toyota - because of the 2003 supplemental restraint system (SRS) electronic control module (ECM) safety recall notice that I received 2 weeks ago, made an appointment 2 days ago with the dealer for this recall - said to come in today at 2:00 pm for the repair. One hour and 45 minutes later - fix was not completed because they said that toyota corporation only allows for 12 sub-wire harness (filters) to be installed each day at each dealer through out the united states of america. They did not that the part and told me at the beginning of the service that they didn't have the part - but still needed to check my car to see if it needed to be repaired. They will have the part tomorrow and will fix tomorrow - hopefully. So my complaint is why does toyota not send the parts to the dealers to fix this safety recall and what will the NHTSA do about this problem with no parts from toyota to fix the problem - only 12 per day per dealer? Also I don't no if this is related but the passenger door lock doesn't work - when it rains it might or not work - problem occurred in 2005 and until this day…
Also reported on the 2003 Toyota Corolla
Other engine problem
Other speed control problem
Airbag inflator rupture
Other powertrain problem
Seat belt or retractor failure
Other body or interior problem
How far this goes
Complaints are voluntary, so 14 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 control module (ecm/pcm/bcm) failure happen on the 2003 Toyota Corolla?
Across 11 owner reports that included an odometer reading, half were filed by 100,000 miles. A quarter were filed before 80,000 miles and a quarter after 130,000 miles. These are the mileages owners reported when they complained, not a prediction for any individual car.
How common is control module (ecm/pcm/bcm) failure on the 2003 Toyota Corolla?
14 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