Only if a disc is significantly and obviously worn, or insecure, cracked or otherwise likely to fail. Being worn below the manufacturer's recommended limit isn't a reason to fail on its own.
Testers grade each defect: a major or dangerous defect fails the MOT, a minor one passes but is written on the certificate.
| Defect | Result |
|---|---|
| Brake disc or drum significantly and obviously worn | FailsMajor |
| Brake disc or drum insecure, fractured or otherwise likely to fail | FailsDangerous |
| Contaminated with oil, grease etc. | FailsMajor |
| Missing | FailsDangerous |
| Brake drum back plate insecure | FailsMajor |
From DVSA's MOT inspection manual for cars and passenger vehicles. Contains public sector information licensed under the Open Government Licence v3.0.
In 2025, 246,780 car MOTs failed on brake discs: 0.78%, or about 1 in 130. 29% of those failures were for a dangerous defect. Testers also noted it as an advisory on 3,514,725 MOTs: something to keep an eye on that didn't fail the test.
Share of the MOTs that failed on brake discs. One MOT can fail for more than one reason.
Share of car MOTs in each mileage band that failed on brake discs.
0.97% of MOTs on cars registered in 2005 failed on brake discs, against 0.18% for cars registered in 2022.
Models that failed on brake discs at least 1.15 times as often as the average car of the same age and mileage, out of 98 with at least 30 MOTs failed on it.
Least often: BMW X3 (0.3×), Audi Q5 (0.3×), BMW 5 Series (0.3×), BMW X1 (0.4×), Tesla Model 3 (0.4×).
Only if badly worn or damaged
In 2025, 246,780 car MOTs failed on brake discs, about 1 in 130. 29% of those were rated dangerous.
1 in 130car MOTs failed on brake discs in 2025
Only if a disc is significantly and obviously worn, or insecure, cracked or otherwise likely to fail. Being worn below the manufacturer's recommended limit isn't a reason to fail on its own.
In 2025, 246,780 car MOTs failed on brake discs: 0.78%, or about 1 in 130. 29% of those failures were for a dangerous defect.
Against the average car of the same age and mileage, the MG HS (5.1 times as often), MG ZS (4.1 times as often) and Peugeot 2008 (2.5 times as often), going by 2025 MOT results.