Model Reports 4 min read Updated 18 Oct 2026

MG TF 2003: reliability & common MOT faults

In 2025, 66 in every 100 first MOTs on a 2003 MG TF were passes. Most common reason for a fail: Handbrake efficiency below minimum (roller test).

Summary

A 2003 MG TF passed first time about 3 in every 100 less often than the average of the 2002 and 2004 model years.

At a glance

How 2,342 first tests went in 2025.

Passed first time
66 in every 100
Did not pass first time
34 in every 100798 failed first-attempt tests
The typical car
22 yearsabout 59,863 miles
First tests counted
2,342

What failed most often

  1. Handbrake efficiency below minimum (roller test)21 in every 100 failed tests
  2. Petrol emissions (with catalyst)18 in every 100 failed tests
  3. Horn11 in every 100 failed tests

How we count this. Data: UK MOT open data, 2025. Only Class 4 cars on their first MOT of the year are counted. A car that fails and is fixed at the test station still counts as a fail in the first-attempt rate. These are raw results, not adjusted for age, mileage, or peer mix. The MOT does not test engine or gearbox internals.

Note:

These are patterns across 2003 MG TF vehicles in 2025, not a prediction that any one car will have them. Faults are grouped by part of the car. A wear pattern follows age and use more than the way the car was built. They come from MOT defect codes, not manufacturer bulletins, recalls or a diagnosis of any one car.

Suspension

Three faults. The strongest is the suspension arm (front): 26 times as often as on similar cars.

Figures below are measured across the 797 of 798 failed first attempts (99.9%) that recorded an odometer reading in 2025. Mileage is needed to compare like with like.

We only list faults with at least 20 failures and a rate of about 2.0 times that of similar cars, which keeps one-off results out of the list.

Suspension arm (front)

Failed on 57 first tests26 times as often as similar carsLikely evidence

What it means

A missing bump stop rubber is not a reason to fail a suspension arm. A component that is fractured, missing or likely to fail is graded Dangerous, and one excessively damaged or corroded is Major. On some vehicles, some highly stressed parts are thin pressed steel, and many of those have hollow box sections or up-facing areas that can collect road dirt and salt, so they get special attention.

Suspension sub-frame mounting area (rear)

Failed on 22 first tests11 times as often as similar carsPossible evidence

What it means

Structure around a sub-frame mounting that is so weakened that control of the vehicle is likely to be adversely affected is graded Dangerous, whether it is damaged, fractured, corroded or inadequately repaired. It is Major when strength is significantly reduced by excessive corrosion, damage or a fracture, or when it is inadequately repaired.

Wheel bearings (front)

Failed on 20 first tests2.0 times as often as similar carsPossible evidence

What it means

Excessive play in a wheel bearing, or a bearing that is excessively rough, is Major. Play so excessive that the bearing is likely to break up or directional control is impaired is Dangerous, and so is a bearing so rough that it is likely to overheat or break up.

Also noted as an advisory

Testers also noted it as an advisory, worn but not yet failing, on 32 first tests, 3.2 times as often as on similar cars.

Data: UK MOT open data, 2025. Compared with cars of the same age and mileage. Advisories count notes recorded on failed first tests only.

Lamps and electrical

One fault: horn, 7.5 times as often as on similar cars.

Horn

Failed on 89 first tests7.5 times as often as similar carsLikely evidence

What it means

A horn that does not work, or is likely to be confused with an emergency vehicle siren, is graded Major. Gongs, bells, sirens and anything with more than one tone, which includes a horn that alternates between its notes, are not allowed, except a gong, bell or siren on vehicles first used before a set date. Sound defects are Minor for named cases such as a bell or harsh sound, and Major under a general row.

Data: UK MOT open data, 2025. Compared with cars of the same age and mileage.

Brakes

Two faults and one wear pattern. The strongest is the brake discs (rear): 4.8 times as often as on similar cars.

Brake discs (rear)

Failed on 23 first tests4.8 times as often as similar carsWear pattern

What it means

A brake disc or drum must be significantly worn before it is rejected, and being worn below the manufacturer's recommended limits is not a reason in itself. Significantly and obviously worn is Major, as is contamination with oil or grease. A disc or drum that is fractured, insecure, seriously weakened or missing is graded Dangerous.

Also noted as an advisory

Testers also noted it as an advisory, worn but not yet failing, on 120 first tests, 3.2 times as often as on similar cars.

Brake efficiency below minimum (roller test)

Failed on 63 first tests4.2 times as often as similar carsLikely evidence

What it means

Service brake efficiency below the minimum requirement is Major, and efficiency less than half of the required value is graded Dangerous. On a roller brake tester, if more than half of the wheels of a brake system lock, the efficiency requirement for that system counts as met.

Handbrake efficiency below minimum (roller test)

Failed on 168 first tests4.0 times as often as similar carsLikely evidence

What it means

A parking brake with efficiency below the minimum requirement is Major, and graded Dangerous where efficiency is less than half of the required value. On a roller brake tester, the requirement counts as met if more than half of the wheels of a brake system lock. The check applies only to vehicles whose parking brake was not already tested as the secondary brake.

Data: UK MOT open data, 2025. Compared with cars of the same age and mileage. Advisories count notes recorded on failed first tests only.

Noise, emissions and leaks

One fault: petrol emissions (with catalyst), 2.9 times as often as on similar cars.

Petrol emissions (with catalyst)

Failed on 140 first tests2.9 times as often as similar carsPossible evidence

What it means

Emissions levels over the manufacturer's specified limits are Major, as are levels over default limits, which apply when no exact match is found for the vehicle. Dense blue or clearly visible black smoke at idle, held for a set period, is Major, except for certain older vehicles and two stroke engines where smoke is unavoidable. An induction or exhaust leak that could affect emissions levels is Major too.

Data: UK MOT open data, 2025. Compared with cars of the same age and mileage.

Seat belts and restraints

One fault: airbag warning light, 2.1 times as often as on similar cars.

Airbag warning light

Failed on 46 first tests2.1 times as often as similar carsPossible evidence

What it means

The airbag warning lamp (SRS MIL in DVSA's wording) is failed only if it indicates a system malfunction, which is Major. A lamp lit to show the passenger airbag is disabled is not to be regarded as a defect. Dashboard messages are not a defect in their own right, though they can help the tester confirm a malfunction.

Data: UK MOT open data, 2025. Compared with cars of the same age and mileage.

Advisories

Other things testers noted as worn or close to failing, more often than on similar cars.

An advisory is a note from the tester about something that has not failed yet. It is an early warning, not a fail. Advisories for the faults above are shown with those faults.

Suspension arm ball joint (rear)

Noted on 24 first tests48 times as often as similar carsElevated evidence

Track rod end (front)

Noted on 43 first tests4.4 times as often as similar carsElevated evidence

Suspension sub-frame (rear)

Noted on 95 first tests2.8 times as often as similar carsElevated evidence

Suspension sub-frame (front)

Noted on 60 first tests2.6 times as often as similar carsElevated evidence

Brake performance (roller test, rear)

Noted on 45 first tests2.4 times as often as similar carsElevated evidence

Suspension arm pins and bushes (rear)

Noted on 23 first tests2.1 times as often as similar carsElevated evidence

Data: UK MOT open data, 2025. Counts cover advisories recorded on failed first tests only, compared with cars of the same age and mileage.

MOT pass rates

How first tests ended, and how the pass rates are counted.

Passed first time
66in every 100
Passed on the first test.
Fixed at the station
5in every 100
Failed, then fixed at the test station the same day.
Failed
29in every 100
Did not pass, and were not fixed at the test station.

First-attempt pass 65.9% of 2,342 first tests (2025): only cars that passed first time count. Official-style pass 71.1%: cars fixed at the test station also count as a pass. The 5 fixed and the 29 not fixed make the 34 in every 100 that did not pass first time.

Same model, other years

Passed first time in every 100, all tested in 2025.

YearPassed first timeFirst tests
200269 in every 1001,553
2003 This car66 in every 1002,342
200469 in every 1002,257
200572 in every 1001,094

Newer cars are younger, so look for a jump rather than the climb.

If you are buying one

What this year's MOT record means for the decision in front of you.

Mileage matters most on a 2003 MG TF.

Of 2003 MG TF vehicles with under 40,000 miles, 81 in every 100 passed their 2025 MOT first time. With 80,000 miles or more, 58 in every 100 did.

Under 40,000479 tests
81
40,000–53,000439 tests
69
53,000–66,000 Typical car495 tests
63
66,000–80,000448 tests
58
80,000 and over480 tests
58

What to check at your mileage

How often each fault turned up on a failed first test, by the car's mileage. Read it as: what is likely to need looking at on a car like the one in front of you.

Under 40,00053,000–66,00080,000 and over
Handbrake efficiency below minimum (roller test)4.47.98.5
Petrol emissions (with catalyst)1.96.58.5
Horn4.05.32.7
Windscreen washers0.82.62.7
Brake efficiency below minimum (roller test)1.93.43.3

Faults per 100 first tests, by the car's mileage at the test.

When a car fails

30in every 100

of failed cars had one item to fix.

44in every 100

of failed cars had three or more items to fix.

7in every 100

of all first tests had a defect the tester marked dangerous (unsafe to drive away).

Every figure here is a first-attempt MOT rate from DVSA open data for this model line, for cars of this model year tested in 2025. Each mileage band holds a fifth of the tests. MOTs do not test engine or gearbox internals, so this is a pre-purchase checklist, not a full reliability score.

FAQs

Short answers about how to read this model-year guide.

A 2003 MG TF passed first time about 3 in every 100 less often than the average of the 2002 and 2004 model years. In 2025, 65.9% of 2,342 first MOTs on the 2003 MG TF passed first time (PRS: items fixed at the station the same day, counted as a fail). The official-style rate including PRS is 71.1%. Among 798 failed first-attempt MOT tests (test year 2025), Suspension arm (front) appears more often than on similar cars (7.2% of those tests; 57 observed failures; about 26× more often than similar cars). There is no single reliability score here; this is a pre-purchase checklist built from DVSA open data, not a guarantee for any individual car.
Ranked by how often they were actually recorded, the items that most often failed a 2003 MG TF at the first attempt were Handbrake efficiency below minimum (roller test) (21.1%), Petrol emissions (with catalyst) (17.6%) and Horn (11.2%), each as a share of the year's failed first attempts. That is what goes wrong most often on the car. The common faults table shows a different measure: faults that are unusual compared with similar cars.
Among failed first-attempt tests we highlight patterns that appear more often than on similar cars. Top example: Suspension arm (front) (7.2% of those tests; 57 observed failures; about 26× more often than similar cars). These are statistical signals, not a diagnosis of any individual car.
Suspension arm (front) shows up more often than on similar cars (7.2% of those tests; 57 observed failures; about 26× more often than similar cars). That does not prove a design fault. Age, mileage, and how the car was used still matter. Treat it as a pre-purchase checkpoint, not a manufacturer service bulletin.
Common MOT problem areas for the 2003 MG TF include Suspension arm (front), Suspension sub-frame mounting area (rear), Horn. These are the faults that stand out compared with similar cars, not a complete list of what can go wrong on any individual car.
Advisories flag issues noted at the test and are not a fail rate. We show advisory patterns that appear more often than on similar cars among failed first-attempt tests, separate from common failure rows. Use them as early-warning checks, not as a pass/fail score.
This page highlights MOT failure patterns for the 2003 MG TF (registration year) using UK DVSA open data for the selected test year. Patterns are compared with cars of a similar age and mileage. It is a buyer checklist from MOT defect statistics, not a full service history or manufacturer service-bulletin list.
No. MOT tests do not cover engine internals, gearboxes, or many electronic modules. Patterns here come from MOT defect statistics only and should not be read as engine or gearbox reliability scores.

About this data

How this page is built and what it can (and can't) say.

These figures come from UK MOT open data for this model year. We surface common failure patterns against similar cars, not a full reliability score, and not a pass/fail verdict on any individual vehicle.

2024 2025

What we include

UK Class 4 cars only. Normal MOT tests (not retests); first test per vehicle per calendar year; results pass, PRS, or fail.

Same-day repairs

PRS means the car failed items that were fixed at the test station and then passed the same day. We count PRS as a first-attempt fail in headline rates so same-day repairs do not hide problems.

How we compare

We compare this model year with other Class 4 cars of similar age and mileage in the same test year. This model family is left out of the peer group so the car is not measured against itself.

What this does not cover

  • MOTs do not cover engine internals, gearboxes, or many electronics; this is not a full reliability score.
  • Common faults come from MOT defect stats, not manufacturer TSBs or recalls.
  • Age and mileage matching reduces, but does not remove, differences in how cars were used and maintained.
  • If the data for a car is too thin to say anything useful, we say so rather than guess.

Contains public sector information licensed under the Open Government Licence v3.0.

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