Airbag warning light at the MOT: which cars fail on it most
1.6% of failed initial MOT tests in 2025 recorded this defect: 142,694 of 9,185,328. By age, it was most common on vehicles 20 years old and over (3.0%) and least common on vehicles 3 to 5 years old (0.8%).
It is one of the 10 most common MOT failures on 19 of the 332 car models we cover. Against vehicles of the same age, it was most common on the SEAT Tarraco, the Fiat Auto Trail and the Fiat Swift. On the SEAT Tarraco, 14.3% of failed tests had it, against 1.0% for all vehicles of the same age.
The DVSA records it as “SRS malfunction indicator lamp warning lamp indicates a fault”. A failed test can have several defects.
What the MOT checks
The warning lamp for the airbag system (the supplementary restraint system, SRS) shows a fault.
The MOT inspection manual lists “An SRS malfunction indicator lamp (MIL) indicates a system malfunction” as a major defect, so the vehicle fails.
The manual also says: “A lamp illuminated to indicate the passenger airbag is disabled is not to be regarded as a defect.”
Car models where it is most common
| # | Car | Share of failed tests | Against same age |
|---|---|---|---|
| 1 | SEAT Tarraco1,170 failed tests | 14.3%167 tests | 14.4×all: 1.0% |
| 2 | Fiat Auto Trail652 failed tests | 11.8%77 tests | 11.9×all: 1.0% |
| 3 | Fiat Swift705 failed tests | 10.8%76 tests | 11.7×all: 0.9% |
| 4 | Skoda Enyaq1,154 failed tests | 8.5%98 tests | 10.2×all: 0.8% |
| 5 | MG 36,120 failed tests | 6.3%386 tests | 6.5×all: 1.0% |
| 6 | Cupra Formentor1,628 failed tests | 5.4%88 tests | 6.5×all: 0.8% |
| 7 | Mercedes-Benz A-Class77,678 failed tests | 6.4%4,974 tests | 5.2×all: 1.2% |
| 8 | SEAT Mii4,453 failed tests | 5.8%257 tests | 4.8×all: 1.2% |
| 9 | Land Rover Range Rover Sport23,917 failed tests | 6.8%1,632 tests | 4.5×all: 1.5% |
| 10 | Mercedes-Benz CLA14,599 failed tests | 4.4%637 tests | 4.5×all: 1.0% |
| 11 | BMW Z33,303 failed tests | 10.5%346 tests | 4.0×all: 2.6% |
| 12 | BMW i33,412 failed tests | 3.3%113 tests | 3.5×all: 0.9% |
| 13 | Land Rover Range Rover16,887 failed tests | 5.9%991 tests | 3.4×all: 1.7% |
| 14 | BMW Z47,735 failed tests | 6.6%513 tests | 2.9×all: 2.3% |
| 15 | Nissan Almera4,501 failed tests | 9.4%423 tests | 2.8×all: 3.3% |
Only models where this defect is one of their 10 most common MOT failures, with at least 50 failed tests, have a figure. So a model that isn't listed can still have it, just less often than its other faults. Vans, pick-ups and taxis are left out, as in our rankings. × is the model's share divided by the share for all vehicles of the same age.
How common it is by car age
- Under 3 years, first used 2023 to 20241.1% of failed tests, against 1.6% for all ages118 failed tests
- 3 to 5 years, first used 2020 to 20220.8% of failed tests, against 1.6% for all ages5,562 failed tests
- 6 to 9 years, first used 2016 to 20191.0% of failed tests, against 1.6% for all ages20,069 failed tests
- 10 to 14 years, first used 2011 to 20151.4% of failed tests, against 1.6% for all ages46,833 failed tests
- 15 to 19 years, first used 2006 to 20102.1% of failed tests, against 1.6% for all ages45,782 failed tests
- 20 years and over, first used 1985 to 20053.0% of failed tests, against 1.6% for all ages24,330 failed tests
All-vehicle figures cover vehicles first used from 1985 to 2024: 9,185,328 of the 9,193,164 failed initial tests in 2025.
How these figures are counted
These are failures recorded at initial MOT tests in 2025. Retests are not counted. A defect found on more than one wheel, lamp or joint at the same test counts once. "Same age" is the defect's share of failed tests for all vehicles first used in the same years, weighted by the model's own failed tests in each year.
An MOT checks safety and emissions on the day of the test. These figures show where a defect was recorded, not why, and not what a repair costs. Figures: DVSA anonymised MOT tests and results, 2025. Contains public sector information licensed under the Open Government Licence v3.0. What the MOT checks: MOT inspection manual: cars and passenger vehicles, GOV.UK, read 1 Nov 2026.
How we choose and rank these defects