What an MOT brake imbalance failure means, common causes and the checks or repairs a garage may need to carry out before a retest.
Brake imbalance means the left and right brakes on the same axle are producing meaningfully different braking effort during the MOT brake test. It is a measurement result, not the name of one failed component.
A sticking caliper, seized slider, wheel cylinder fault, contamination, uneven friction material, hydraulic restriction or adjustment issue can all create an imbalance. The exact cause depends on whether the affected axle uses discs, drums or an electronic parking-brake arrangement.
The garage will usually compare both sides of the axle and look at pad or shoe condition, disc or drum condition, free movement of calipers or cylinders and the hydraulic system. Repairing only the side with the lower reading without checking why it differs can miss the real cause.
Not necessarily. The MOT has identified that braking effort is uneven beyond the permitted test criteria. Because braking is safety-critical, the defect still needs proper investigation rather than being treated as a paperwork issue.
Enter the registration to import the latest DVSA MOT items, or paste the wording, and AutoAid will explain each item separately.
Translate my MOTSee common MOT failures →AutoAid explains MOT wording in plain English, but the tester's recorded defect and a physical inspection take precedence.