MG 3 MOT pass rate & common failures

At a glance

Recorded pass rate

We are not publishing a ranking for the 3. The examples tested do not cover a wide enough spread of ages and mileages to compare it fairly, and an unadjusted pass rate mostly sorts models by how recently they were bought rather than how well they were built. The failure and advisory patterns below come from the same 24,958 tests and are worth reading on their own terms.

DVSA recorded wording

Most common failure items

Share of failed MG 3 tests in which each item was recorded. One failed test often lists several items, so these do not sum to 100%.

1. 1.Tyre tread depth not in accordance with the requirements11.8%

   565 occurrencesTyre worn close to the legal limit explained

2. 2.Wiper blade missing or obviously not clearing the windscreen11.8%

   563 occurrencesWiper or washer not working properly explained

3. 3.A tyre cords visible or damaged10.9%

   521 occurrencesTyre ply or cord exposed, or the casing separating explained

4. 4.A suspension pin, bush or joint excessively worn10.6%

   507 occurrencesSuspension arm bush worn explained

5. 5.A tyre seriously damaged9.1%

   436 occurrencesTyre damaged or deteriorated explained

6. 6.A spring or spring component fractured or seriously weakened8.9%

   425 occurrencesRoad spring broken or fractured explained

7. 7.Parking brake efficiency below minimum requirement8.4%

   402 occurrencesParking brake efficiency too low explained

8. 8.Brake pipe damaged or excessively corroded7.7%

   370 occurrencesBrake pipe corroded explained

9. 9.A brake lining or pad worn below 1.5mm7.7%

   369 occurrencesBrake drum or shoe worn or contaminated explained

10. 10.An SRS malfunction indicator lamp (MIL) indicates a system malfunction7.5%

    360 occurrencesAirbag warning lamp on, or airbag missing explained

Warnings without a failure

Most common advisories

Share of all MG 3 tests carrying each advisory. The denominator differs from the failure list above because an advisory can be issued on a car that passed.

1. 1.Tyre tread depth not in accordance with the requirements24.5%

   6,122 testsTyre worn close to the legal limit explained

2. 2.A tyre seriously damaged17.9%

   4,464 testsTyre damaged or deteriorated explained

3. 3.Brake disc or drum excessively weakened, insecure or fractured11.9%

   2,972 testsBrake disc worn, pitted or scored explained

4. 4.A suspension pin, bush or joint excessively worn9.6%

   2,408 testsSuspension arm bush worn explained

5. 5.A brake lining or pad worn below 1.5mm8.1%

   2,026 testsBrake drum or shoe worn or contaminated explained

6. 6.Brake pipe damaged or excessively corroded6.8%

   1,702 testsBrake pipe corroded explained

7. 7.A suspension component excessively damaged or corroded5.6%

   1,394 testsSuspension mounting corroded or insecure explained

8. 8.A suspension component excessively damaged or corroded5.2%

   1,309 testsSuspension mounting corroded or insecure explained

How wear changes the picture

Pass rate by vehicle age

Bands holding too few tests to be meaningful are omitted rather than shown as a rate.

What gets tested

The 3 fleet

Average mileage recorded at test

38,948

Across examples of every age, so this is a description of the fleet rather than an annual figure.

Fuel mix of tested cars

Petrol99.9%

Compare within the range

Other MG models

• MG ZS — 82.1% unadjusted
• MG HS — 88.3% unadjusted
• MG 5 — 84.3% unadjusted
• MG TF — 69.6% unadjusted
• MG Mgf — 66.9% unadjusted
• MG 4 — 88.8% unadjusted
• All MG models →

Common questions

How reliable is the MG 3 compared with other cars?

We do not publish a comparison for the MG 3, because the cars of this model that have been tested do not cover a wide enough range of ages and mileages. Its raw pass rate is 75.1% across 24,958 tests, but comparing a raw rate between models mostly ranks them by how new they are rather than how good they are. The failure and advisory patterns further down the page are still drawn from real tests and are worth reading.

What is the most common MOT failure on a MG 3?

The item recorded most often is "Tyre tread depth not in accordance with the requirements", which appears in 11.8% of failed MG 3 tests. Because one failed test can list several items, these shares do not add up to 100%.

What do testers most often warn about on a MG 3?

The most common advisory is "Tyre tread depth not in accordance with the requirements", noted on 24.5% of all MG 3 tests. An advisory is not a failure: it flags something that will likely need attention before the next test.

What mileage does a MG 3 usually have at its MOT?

The average odometer reading recorded at test is 38,948 miles. This is the mileage across all tested examples of every age, not an annual figure, so treat it as a description of the fleet rather than a target for one car.

Does a MG 3 get harder to pass as it ages?

Yes. At 3 to 5 years old, 82.8% of MG 3 tests pass. By 12 to 14 years, that falls to 61.4%. Nearly every model follows this pattern, which is why comparing raw pass rates between models is misleading unless age is accounted for.

How this was worked out

Method and limits

Figures come from the DVSA anonymised MOT testing dataset, published under the Open Government Licence. Only class 4 initial tests are counted: retests are excluded so a car appears once, and abandoned tests are excluded entirely. No adjusted rate is shown because this model's tested examples do not cover enough of the national age and mileage range for standardisation to mean anything.

An MOT measures whether a car met a legal standard on the day. It is not a breakdown record, a service history or a running-cost estimate, and a pass rate is a property of a fleet rather than a prediction about one car.

Further reading

Make sense of the numbers

• How to judge reliability from evidence rather than reputation
• What counts as high or low mileage for a car’s age
• The most common MOT failures and how to avoid them
• What to check before buying a used MG