2017 Toyota Mirai: what breaks, and at what mileage
What breaks on the 2017 Toyota Mirai
Only 6 defect reports have been filed with NHTSA about the 2017 Toyota Mirai, which is too few to compute mileage percentiles or a risk score. The reports reported other driver assistance problem.
When each failure gets reported
Tick median reported mileage Solid middle half of reports Faint 10th to 90th percentile Colour how bad the failure is when it happens
How reports accumulate
Every report with an odometer reading, cumulative, from 0 to 200,000 miles. A curve that climbs early is a car with early problems, whatever its total.
- Line share of reports filed by that mileage
Every reported failure mode
| Failure mode | System | Reports | With reading | 25th | Median | 75th | Per 1,000 | Typical repair | Severity |
|---|---|---|---|---|---|---|---|---|---|
| Other driver assistance problem | adas | 2 | 0 | — | — | — | 0.1 | $250–$1,800 | High |
| Radiator or coolant leak | cooling | 1 | 1 | — | 20k | — | 0.1 | $350–$1,900 | High |
| Other brake problem | brakes | 1 | 0 | — | — | — | 0.1 | $300–$1,800 | High |
| Other visibility problem | glass | 1 | 1 | — | 1k | — | 0.1 | $150–$1,400 | Moderate |
| Unclassified problem | other | 1 | 1 | — | 100 | — | 0.1 | — | Moderate |
This year had no usable recall paperwork, so the fleet-size estimate is the median of other years of the same model. Repair costs are typical independent-shop ranges for the failure, not figures from these reports.
What owners wrote
Verbatim from NHTSA complaint narratives, trimmed for length. The odometer reading is the one the owner gave.
Radiator or coolant leak
Until two (2) days ago, I was the happy owner of a 2017 toyota mirai (VIN [xxx]). At the time of my incident, the car had approximately 19,700 miles on the odometer. On friday 24 august 2018 at approximately 1615 (4:15 pm), I was driving my wife to the cleaners. I was on almaden expressway just south of the camden intersection in a southerly direction. Suddenly and without warning, the car lost power. The car monitor screen instructed me to pull off as soon as possible and to contact my car dealer. I was informed that I had an fc failure. After the car was towed to the dealer, I was informed by the dealer that a small rock had completely passed through the radiator. The toyota mirai is a hydrogen fuel cell vehicle. There is no internal combustion engine. Hydrogen fuel feeds a fuel cell which combines the hydrogen with free oxygen to make electricity. This electricity then powers two motors and/or the battery. The fuel cell requires a radiator for cooling. This radiator is the achilles heel of the mirai. It is placed low, in front, on the passenger?s side of the vehicle. There is no bumper to protect it from collisions with curbs…
Every year of the Toyota Mirai
Scores compare each year against other cars of the same model year, so a low number on an older car is a real result and not an artefact of age.
Shorter is better. Years with too few reports to score are shown without a bar rather than as a zero, because no data is not good news.
What the reports on file say
The complaints recorded against the 2017 Toyota Mirai are other driver assistance problem (2 reports), radiator or coolant leak (1 report, around 20k miles), other brake problem (1 report) and other visibility problem (1 report, around 1k miles). With a sample this size these are anecdotes rather than a pattern, and they are shown because somebody looking at this exact car would rather see them than nothing.
Why this page is short
A model year needs about 8 reports before percentiles mean anything, and this one does not have them. Complaint volume tracks how many cars were sold and how long they have been on the road, so a thin page usually means a rare car, a new car, or a car whose owners do not file.
Other years of the same model do have enough: 2022. The mechanical parts are often shared across those years, so their pages are the better guide to what this one is likely to do, with the caveat that a shared part is not a shared production line.
Where this comes from. Every figure above is computed from NHTSA owner complaints and recall records for this exact make, model and year. Complaints are voluntary and self-selected, so treat counts as a floor. The methodology page writes out each formula, and the same numbers are available as JSON.
What breaks at my mileage Compare with another car
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