DVSA defectMajor

`1.4.1.a`

Performance · Parking brake performance and efficiency

Major · Rectify before re-test.

What this code means

Parking brake inoperative on one side, or in the case of testing on the road, the vehicle deviates excessively from a straight line

DVSA manual phrasing — written for testers, kept verbatim.

How serious is itMajor

May affect the vehicle's safety, put other road users at risk, or have an impact on the environment. The vehicle has failed the MOT.

What the tester was checking

Performance

Section 1: Brakes
1.4: Parking brake performance and efficiency
1.4.1: Performance
1.4.1.a: this defect

What to do next

Rectify before re-test.

Always confirm with a qualified MOT tester or vehicle technician for your specific vehicle. A re-test must address the defect category identified above.

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.