SEAT Leon 2004: reliability & common MOT faults

At a glance

How 1,048 first tests went in 2025.

Passed first time: 61 in every 100
Did not pass first time: 39 in every 100408 failed first-attempt tests
The typical car: 21 yearsabout 133,778 miles
First tests counted: 1,048

What failed most often

Handbrake efficiency below minimum (roller test)13 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.

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.

Exhaust system

Noted on 44 first tests2.2 times as often as similar carsElevated evidence

Brake performance (roller test, rear)

Noted on 25 first tests2.2 times as often as similar carsElevated evidence

Brake discs (rear)

Noted on 58 first tests2.0 times as often as similar carsWear pattern

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: 61in every 100; Passed on the first test.
Fixed at the station: 8in every 100; Failed, then fixed at the test station the same day.
Failed: 31in every 100; Did not pass, and were not fixed at the test station.

First-attempt pass 61.1% of 1,048 first tests (2025): only cars that passed first time count. Official-style pass 69.4%: cars fixed at the test station also count as a pass. The 8 fixed and the 31 not fixed make the 39 in every 100 that did not pass first time.

Petrol and diesel

First testsPassed first time, as tested

Petrol69262

Diesel35359

Figures are in every 100 first tests.

Same model, other years

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

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

Year	Passed first time	First tests
2002	61 in every 100	397
2003	63 in every 100	817
2004 This car	61 in every 100	1,048
2005	60 in every 100	1,198
2006	55 in every 100	1,950
2007	59 in every 100	3,078
2008	60 in every 100	3,533
2009	59 in every 100	3,891
2010	61 in every 100	4,828
2011	63 in every 100	5,583
2012	65 in every 100	7,838
2013	71 in every 100	10,755
2014	76 in every 100	17,542
2015	79 in every 100	16,225
2016	80 in every 100	15,083
2017	78 in every 100	17,384
2018	78 in every 100	20,120
2019	77 in every 100	18,377
2020	84 in every 100	12,952
2021	87 in every 100	10,653
2022	89 in every 100	3,314

FAQs

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

Is the 2004 SEAT Leon reliable?

The 2004 SEAT Leon follows the pattern of the model years either side. Its main cause of failure was Handbrake efficiency below minimum (roller test), about 13 in every 100 failed tests. In 2025, 61.1% of 1,048 first MOTs on the 2004 SEAT Leon passed first time (PRS: items fixed at the station the same day, counted as a fail). The official-style rate including PRS is 69.4%. Among 408 failed first-attempt MOT tests (test year 2025), we highlight MOT failure patterns that show up more often than on cars of a similar age and mileage when the sample is large enough to trust. 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.

What is most likely to fail on a 2004 SEAT Leon?

Ranked by how often they were actually recorded, the items that most often failed a 2004 SEAT Leon at the first attempt were Handbrake efficiency below minimum (roller test) (13.0%), 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.

How should I read advisories vs fails?

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.

What does this SEAT Leon 2004 MOT report cover?

This page highlights MOT failure patterns for the 2004 SEAT Leon (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.

Does this include engine and gearbox problems?

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.