1.3.1.b.ii
Performance · Secondary brake performance and efficiency
Dangerous · Vehicle is legally undriveable until rectified.
Brakes imbalance across an axle such that the braking effort from any wheel is less than 50% of the maximum effort recorded from the other wheel on a steered axle
DVSA manual phrasing — written for testers, kept verbatim.
A direct and immediate risk to road safety, or that has a serious impact on the environment. The vehicle should not be driven until repaired.
Performance
- Section 1
- Brakes
- 1.3
- Secondary brake performance and efficiency
- 1.3.1
- Performance
- 1.3.1.b.ii
- this defect
Vehicle is legally undriveable until rectified.
Always confirm with a qualified MOT tester or vehicle technician for your specific vehicle. A re-test must address the defect category identified above.
Related codes in this subject
motfailcode.uk maps DVSA MOT defect codes to plain-English meanings. Defect severity classifications follow the DVSA MOT Inspection Manual current as of 12 May 2026. Codes and severities are updated annually (typically May). Always confirm with a qualified MOT tester or vehicle technician for your specific vehicle. This site is not affiliated with DVSA or HM Government.
See our methodology for how we extract and verify each code, and sources for the full citation manifest.