Lexus IS 2004: MOT failure rate for its age
35.5% of 12,066 MOT tests of the Lexus IS first registered in 2004 failed at the first attempt (2019–2024; retests excluded). Against this model's own normal rate at the same ages the index is 106.2 (95% CI 103.0–109.4; 100 = normal for this model at that age): the 2004 Lexus IS fails more often than other build years of the same model at the same age.
| Measure | Value | Unit | Compared with | Years | Tests |
|---|---|---|---|---|---|
| Failed first time | 35.5 | % | all ages tested | 2019–2024 | 12066 |
| Index against this model at the same age (95% CI 103.0–109.4) | 106.2 | index | 100 = normal for this model at that age | 2019–2024 | 12066 |
| Rank among this model's 22 build years | 21 | of 22 | 1 = fails least for its age | 2019–2024 | 12066 |
| Tested in 2024 | 1430 | tests | median 105,542 miles | 2024 | 1430 |
Data release dvsa-2024-v2 (24 Sep 2026) · page updated 30 Sep 2026 · full dataset (v5).
How does the 2004 Lexus IS fail at each age?
Cars built in 2004 were tested at ages 15 to 20 between 2019 and 2024. Each row compares their first-time failure share with what this model normally shows at that age, after allowing for the overall failure level of each test year.
| Age | Tests | Failed, % | 95% interval | Normal for this model at that age, % | Index (100 = normal) |
|---|---|---|---|---|---|
| 15 | 2,807 | 36.7 | 35–38.5 | 32.2 | 114 |
| 16 | 2,294 | 36.5 | 34.6–38.5 | 32.3 | 113 |
| 17 | 2,078 | 34.6 | 32.6–36.7 | 33.2 | 104.1 |
| 18 | 1,836 | 35 | 32.8–37.2 | 34.2 | 102.2 |
| 19 | 1,621 | 34.9 | 32.6–37.3 | 34.8 | 100.3 |
| 20 | 1,430 | 33.7 | 31.3–36.2 | 34.8 | 96.8 |
Source: DVSA MOT bulk data · Window: 2019–2024 · n = 12,066 (initial tests) · Method: normal rate = this model's first-time failure share at that age across its build years (cells of 400+ tests), adjusted for each test year's overall level; cells of 30+ tests, under 500 marked rough · Updated: 30 Sep 2026 · Release: dvsa-2024-v2 · CSV
What fails most on the 2004 Lexus IS?
The most common failure group on cars built in 2004 is lamps, reflectors and electrical equipment: 28.4 items per 100 first tests, against 17.3 across all build years of the Lexus IS. These counts are not age-adjusted: cars built in 2004 were tested at ages 15 to 20.
| Failure group | Built 2004, per 100 | All build years, per 100 | Items |
|---|---|---|---|
| Lamps, reflectors and electrical equipment | 28.4 | 17.3 | 3,423 |
| Suspension | 22.6 | 7.2 | 2,729 |
| Tyres | 12.7 | 9.8 | 1,529 |
| Brakes | 12.4 | 10.1 | 1,498 |
| Visibility | 11.7 | 7.7 | 1,413 |
Source: DVSA MOT bulk data · Window: 2019–2024 · n = 12,066 (initial tests of this build year) · Method: failure items grouped by DVSA's top-level defect groups, per 100 initial tests; groups with 30+ items · Updated: 30 Sep 2026 · Release: dvsa-2024-v2 · CSV
How does 2004 compare with the years around it?
Among the 22 published build years of the Lexus IS, 2004 ranks 21 (1 = fails least for its age). 2003: index 103.9. 2005: index 99.3.
| Build year | Index (100 = normal) | 95% interval | Verdict | Tests |
|---|---|---|---|---|
| 1999 | 100.7 | 93.1–108.3 | no different (rough estimate) | 1,800 |
| 2000 | 111.2 | 105.6–116.9 | worse (rough estimate) | 3,615 |
| 2001 | 102.4 | 98.4–106.3 | no different | 6,950 |
| 2002 | 103.3 | 100.0–106.7 | no different | 9,860 |
| 2003 | 103.9 | 100.7–107.1 | worse | 11,302 |
| 2004 | 106.2 | 103.0–109.4 | worse | 12,066 |
| 2005 | 99.3 | 96.2–102.5 | no different | 11,833 |
| 2006 | 98.8 | 96.5–101.1 | no different | 23,659 |
| 2007 | 98.5 | 96.4–100.7 | no different | 28,132 |
| 2008 | 99.8 | 97.1–102.4 | no different | 20,660 |
| 2009 | 97.4 | 94.4–100.4 | no different | 16,669 |
| 2010 | 98.1 | 94.6–101.5 | no different | 14,447 |
| 2011 | 101.6 | 97.0–106.2 | no different | 9,224 |
| 2012 | 93.9 | 87.7–100.0 | no different | 5,394 |
| 2013 | 91.3 | 86.6–96.0 | better | 10,281 |
| 2014 | 98.3 | 94.6–102.0 | no different | 19,406 |
| 2015 | 96.1 | 92.0–100.1 | no different | 17,439 |
| 2016 | 99.5 | 94.4–104.5 | no different | 12,391 |
| 2017 | 91.8 | 85.6–97.9 | better | 8,277 |
| 2018 | 85.8 | 78.7–93.0 | better | 5,903 |
| 2019 | 103.6 | 93.4–113.8 | no different (rough estimate) | 3,635 |
| 2020 | 101.3 | 83.0–119.6 | no different (rough estimate) | 1,157 |
Source: DVSA MOT bulk data · Window: 2019–2024 · n = 254,100 (initial tests) · Method: observed failures against those expected for the same model at the same ages, test-year level adjusted; verdict follows the printed one-decimal bound · Updated: 30 Sep 2026 · Release: dvsa-2024-v2 · CSV
How to cite this page
MOT Risk Index (2026). Lexus IS 2004 MOT statistics (data release dvsa-2024-v2; full dataset motriskindex-families-2024-v5, DOI 10.5281/zenodo.22975051), updated 30 September 2026. motriskindex.co.uk/cars/lexus-is/2004/
How every figure is calculated: methodology. Age, test year and build year are tied together (age = test year − build year), so the test-year level is taken as observed, not estimated.
Other pages for this model
Lexus IS 1999 · Lexus IS 2000 · Lexus IS 2001 · Lexus IS 2002 · Lexus IS 2003 · Lexus IS 2005 · Lexus IS 2006 · Lexus IS 2007 · Lexus IS 2008 · Lexus IS 2009 · Lexus IS 2010 · Lexus IS 2011 · Lexus IS 2012 · Lexus IS 2013 · Lexus IS 2014 · Lexus IS 2015 · Lexus IS 2016 · Lexus IS 2017 · Lexus IS 2018 · Lexus IS 2019 · Lexus IS 2020 · Lexus IS in Finland · Lexus IS by postcode area · Lexus IS body, chassis and structure failures · Lexus IS brakes failures · Lexus IS vehicle identification failures · Lexus IS lamps, reflectors and electrics failures · Lexus IS noise, emissions and leaks failures · Lexus IS road wheels failures · Lexus IS seat belts and airbags failures · Lexus IS steering failures · Lexus IS suspension failures · Lexus IS tyres failures · Lexus IS visibility failures