Model Reports 4 min read Updated 18 Oct 2026

BMW 6 Series 2005: reliability & common MOT faults

In 2025, 69 in every 100 first MOTs on a 2005 BMW 6 Series were passes. Most common reason for a fail: Individual sidelight or tail light (front).

Summary

The 2005 BMW 6 Series follows the pattern of the model years either side.

At a glance

How 1,113 first tests went in 2025.

Passed first time
69 in every 100
Did not pass first time
31 in every 100346 failed first-attempt tests
The typical car
20 yearsabout 110,516 miles
First tests counted
1,113

What failed most often

  1. Individual sidelight or tail light (front)14 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 2005 BMW 6 Series 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.

Suspension

Two faults. The strongest is the coil spring (rear): 3.0 times as often as on similar cars.

Figures below are measured across the 346 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.

Coil spring (rear)

Failed on 30 first tests3.0 times as often as similar carsLikely evidence

What it means

A missing bump stop rubber is not a reason to fail a coil spring. When the vehicle is jacked and lowered, a spring that does not correctly locate as the suspension returns to its normal running position is rejected as insecurely attached. A missing spring is Major, and graded Dangerous where directional control is affected.

Anti-roll bar linkage ball joint dust cover (front)

Failed on 35 first tests2.5 times as often as similar carsPossible evidence

What it means

A suspension joint dust cover that is severely deteriorated is Minor. It becomes Major once it is missing or no longer prevents the ingress of dirt, so what matters is whether it still keeps dirt out. DVSA words this for any suspension joint dust cover, and files it here under anti-roll bars.

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

Seat belts and restraints

One fault: airbag warning light, 2.5 times as often as on similar cars.

Airbag warning light

Failed on 29 first tests2.5 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.

Suspension arm pins and bushes (rear)

Noted on 58 first tests6.8 times as often as similar carsElevated evidence

Suspension arm ball joint (front)

Noted on 22 first tests2.4 times as often as similar carsElevated evidence

Rigid brake pipes (front)

Noted on 44 first tests2.0 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
69in 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
26in every 100
Did not pass, and were not fixed at the test station.

First-attempt pass 68.9% of 1,113 first tests (2025): only cars that passed first time count. Official-style pass 74.3%: cars fixed at the test station also count as a pass. The 5 fixed and the 26 not fixed make the 31 in every 100 that did not pass first time.

Same model, other years

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

406080100200520102015Newer cars
40608010020052010Newer cars

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

YearPassed first timeFirst tests
200470 in every 100917
2005 This car69 in every 1001,113
200670 in every 1001,283
200774 in every 1001,081
200876 in every 100980
200975 in every 100530
201080 in every 100493
201177 in every 100583
201278 in every 1001,360
201379 in every 1001,784
201478 in every 1001,816
201582 in every 1001,820
201685 in every 1001,726
201784 in every 1001,254
201886 in every 1002,168
201988 in every 100990

FAQs

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

The 2005 BMW 6 Series follows the pattern of the model years either side. Its main cause of failure was Individual sidelight or tail light (front), about 14 in every 100 failed tests. In 2025, 68.9% of 1,113 first MOTs on the 2005 BMW 6 Series passed first time (PRS: items fixed at the station the same day, counted as a fail). The official-style rate including PRS is 74.3%. Among 346 failed first-attempt MOT tests (test year 2025), Coil spring (rear) appears more often than on similar cars (8.7% of those tests; 30 observed failures; about 3.0× 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 2005 BMW 6 Series at the first attempt were Individual sidelight or tail light (front) (14.5%), 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: Coil spring (rear) (8.7% of those tests; 30 observed failures; about 3.0× more often than similar cars). These are statistical signals, not a diagnosis of any individual car.
Coil spring (rear) shows up more often than on similar cars (8.7% of those tests; 30 observed failures; about 3.0× 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 2005 BMW 6 Series include Coil spring (rear), Anti-roll bar linkage ball joint dust cover (front), Airbag warning light. 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 2005 BMW 6 Series (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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