MOT failure rate and common problems for the MG Mg-B, and how to check your own car by registration.

Updated 05 September 2026.

21.1%fail rate

MG Mg-B MOT failure rate

What a MG Mg-B fails its MOT on, and the part that fixes each.

What it fails on, and why

Lamps & electrical35.9% of failures

Lighting is the single most common MOT failure and the cheapest to put right. A blown headlight, brake-light or number-plate bulb, a cracked lens, or a headlamp beam that points too high or low will all fail. Most are a two-minute bulb swap.

Visibility/wipers30.8% of failures

Visibility failures include torn or smearing wiper blades, a washer jet that does not reach the screen, and chips or cracks in the driver's swept area. Blades and washer fluid are quick, cheap fixes.

Suspension23.1% of failures

Suspension failures usually mean a worn or snapped coil spring, a leaking shock absorber, or play in a lower arm ball joint or bush. The tester checks for corrosion, fractures and excessive movement. A broken front spring is one of the most common failures on higher-mileage cars and is a straightforward replacement.

Brakes20.5% of failures

Brake failures cover worn pads and discs, an imbalance between wheels, corroded or scored discs, or a binding caliper. Braking efficiency is measured on a rolling road, so a spongy or pulling brake shows up as a low reading.

Exhaust & emissions12.8% of failures

Exhaust failures cover leaks, insecure mountings and emissions over the limit. A blowing exhaust, a failed lambda reading or a diesel that smokes beyond the limit will fail.

Tyres12.8% of failures

Tyres fail for tread below the 1.6mm legal limit across the central three-quarters, uneven or exposed-cord wear, or sidewall damage. The tester inspects all four; a single illegal tyre is a fail.

The parts that fix each

If your car has just failed, you have 10 working days to fix the items and get a free partial retest. Confirm the exact fitment against your registration or VIN before buying.

For the lamps & electrical failure: MG Mg-B headlight and indicator bulbsShop MG Mg-B headlight and indicator bulbs on Amazonaffiliate Find MG Mg-B headlight and indicator bulbs on eBayaffiliate

For the visibility/wipers failure: MG Mg-B wiper bladesShop MG Mg-B wiper blades on Amazonaffiliate Find MG Mg-B wiper blades on eBayaffiliate

For the suspension failure: MG Mg-B suspension springs and shock absorbersShop MG Mg-B suspension springs and shock absorbers on Amazonaffiliate Find MG Mg-B suspension springs and shock absorbers on eBayaffiliate

For the brakes failure: MG Mg-B brake pads and discsShop MG Mg-B brake pads and discs on Amazonaffiliate Find MG Mg-B brake pads and discs on eBayaffiliate

For the exhaust & emissions failure: MG Mg-B exhaustShop MG Mg-B exhaust on Amazonaffiliate Find MG Mg-B exhaust on eBayaffiliate

For the tyres failure: MG Mg-B tyresShop MG Mg-B tyres on Amazonaffiliate Find MG Mg-B tyres on eBayaffiliate

Other models

All MG models MOT failure rates comparedRanked worst to best MG Zr MOT failures30.2% failure rate MG Mgf MOT failures33.3% failure rate Ford Fiesta MOT failures27.1% failure rate

Questions and answers

What is the MOT failure rate of the MG Mg-B?

It fails 21.1% of its MOT tests across the DVSA record, from 185 tests.

What do these cars fail their MOT on most?

The most common failure area is lamps & electrical, at 35.9% of this model's failures.