Peugeot 308 2020: reliability & common MOT faults

In 2025, 85 in every 100 first MOTs on a 2020 Peugeot 308 were passes. Most common reason for a fail: Tyre condition (front).

Summary

A 2020 Peugeot 308 passed first time about 2 in every 100 more often than the average of the 2019 and 2021 model years.

At a glance

How 3,618 first tests went in 2025.

Passed first time
85 in every 100
Did not pass first time
15 in every 100555 failed first-attempt tests
The typical car
5 yearsabout 37,221 miles
First tests counted
3,618

What failed most often

  1. Tyre condition (front)16 in every 100 failed tests
  2. Headlight (front)10 in every 100 failed tests
  3. Brake pads (front)10 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 2020 Peugeot 308 vehicles in 2025, not a prediction that any one car will have them. Faults are grouped by part of the car. They come from MOT defect codes, not manufacturer bulletins, recalls or a diagnosis of any one car.

Lamps and electrical

One fault: headlight (front), 5.0 times as often as on similar cars.

Figures below are measured across the 555 failed first attempts in 2025 that had a mileage recorded, which allows a like-for-like comparison.

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.

Headlight (front)

Failed on 58 first tests5.0 times as often as similar carsLikely evidence

What it means

On vehicles first used on or after a set date, a halogen headlamp unit converted to take HID or LED bulbs fails for light source and lamp not compatible, which is Major. A complete unit built with those light sources is not failed for that. The precise position of the lamps is not part of the inspection beyond a visual look to see that they sit at about the same height and distance from each side.

Data: UK MOT open data, 2025. 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
85in every 100
Passed on the first test.
Fixed at the station
3in every 100
Failed, then fixed at the test station the same day.
Failed
12in every 100
Did not pass, and were not fixed at the test station.

First-attempt pass 84.7% of 3,618 first tests (2025): only cars that passed first time count. Official-style pass 88.5%: cars fixed at the test station also count as a pass. The 3 fixed and the 12 not fixed make the 15 in every 100 that did not pass first time.

Petrol and diesel

First testsTypical mileagePassed first time, as testedPassed first time, same mileage
Petrol2,69033,263 miles8685
Diesel92457,203 miles8087

Figures are in every 100 first tests. Cars with more miles usually fail more often, so the same-mileage figure gives every fuel the mileage mix of all the cars in this year.

Same model, other years

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

406080100201020152020Older carsNewer cars
40608010020102020Older cars

Newer cars are younger, so look for a jump rather than the climb. A year earlier (2024), when these cars were a year younger, 86 in every 100 passed first time.

YearPassed first timeFirst tests
200745 in every 100556
200849 in every 1005,515
200949 in every 1008,392
201052 in every 1009,728
201157 in every 1008,047
201255 in every 1008,838
201354 in every 1009,434
201462 in every 10011,161
201567 in every 10012,989
201669 in every 10013,556
201772 in every 1008,588
201877 in every 1008,002
201981 in every 1006,840
2020 This car85 in every 1003,618
202183 in every 1001,538
202288 in every 1003,689

If you are buying one

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

Mileage matters most on a 2020 Peugeot 308.

Of 2020 Peugeot 308 vehicles with under 24,000 miles, 93 in every 100 passed their 2025 MOT first time. With 57,000 miles or more, 76 in every 100 did.

Under 24,000736 tests
93
24,000–33,000720 tests
90
33,000–42,000 Typical car715 tests
84
42,000–57,000739 tests
80
57,000 and over708 tests
76

Petrol or diesel?

Typical mileagePassed first time,
as tested
Passed first time,
same mileage
Petrol33,263 miles8685
Diesel57,203 miles8087

Figures are in every 100 first tests. Petrol cars look better on the raw figures only because diesel cars have done more miles (typically 57,203 against 33,263). At the same mileage there is no clear difference between the two.


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 24,00033,000–42,00057,000 and over
Tyre condition (front)1.62.81.8
Headlight (front)0.11.43.1
Brake pads (front)0.02.21.8

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


When a car fails

53in every 100

of failed cars had one item to fix.

16in every 100

of failed cars had three or more items to fix.

5in 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 2020 Peugeot 308 passed first time about 2 in every 100 more often than the average of the 2019 and 2021 model years. In 2025, 84.7% of 3,618 first MOTs on the 2020 Peugeot 308 passed first time (PRS: items fixed at the station the same day, counted as a fail). The official-style rate including PRS is 88.5%. Among 555 failed first-attempt MOT tests (test year 2025), Headlight (front) appears more often than on similar cars (10.5% of those tests; 58 observed failures; about 5.0× 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 2020 Peugeot 308 at the first attempt were Tyre condition (front) (15.7%), Headlight (front) (10.5%) and Brake pads (front) (9.7%), 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: Headlight (front) (10.5% of those tests; 58 observed failures; about 5.0× more often than similar cars). These are statistical signals, not a diagnosis of any individual car.
Headlight (front) shows up more often than on similar cars (10.5% of those tests; 58 observed failures; about 5.0× 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 2020 Peugeot 308 include Headlight (front). These are the faults that stand out compared with similar cars, not a complete list of what can go wrong on any individual car.
This page highlights MOT failure patterns for the 2020 Peugeot 308 (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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