MOT cost .
Mercedes Benz Unclassified
MOT 2024

Photo: Bowe, Jeffrey J United States. Urban Mass Transportation Administration, Public domain

Mercedes Benz

Unclassified

1,961 MOT tests analysed. sits above the UK fleet average — here's where Unclassifieds pass, fail, and end up on the retest sheet.

That's 5.5 points above the UK fleet average across our 1,984 tracked models — a confident result.

Pass

83.0%

Pass-after-fix

2.9%

Fail

13.5%

Avg miles

68,276

Pass + Pass-after-fix + Fail = 100%

ULEZ borderline — check VRM

Some examples of this model are borderline — a small number of diesels were certified Euro 6 before September 2015. Check your registration on the government's ULEZ checker to be certain. Daily charges if driven in the zone: London £12.50 · Birmingham £8.00 · Bristol £9.00 .

UK ULEZ & CAZ guide →

Performance by cohort

3 year bands · 1,961 tests

Pass rate climbs 16.1 points across the cohorts — newer Unclassified examples clear the test more reliably than the early cars.

Pre-2018 cohort 1,470

Pass

80.4%

Fail

15.4%

PRS

3.4%

Avg mileage at test

79,596 mi

2018–2020 cohort 346

Pass

88.4%

Fail

9.8%

PRS

1.7%

Avg mileage at test

41,238 mi

2021+ cohort 145

Pass

96.5%

Fail

3.5%

PRS

0.0%

Avg mileage at test

19,276 mi

Cohort = vehicle's first-registration year band. Same model, different generations of build.

The picture

Unclassified: above-average pass rates, with caveats

Across 860 MOT tests, the Unclassified returns 81.6% first-time pass — above the UK fleet average. The single most-logged Major fail is windscreen damage. A corroded brake pipe and a number-plate lamp out round out the top three. Average tested mileage sits at 81,649, which is the lens to read those failure rankings through. If you own one and the next test is close, the ranked list below is a sensible pre-test checklist.

ABI Insurance Group

Group 28–46

A high-group car — insurance costs will be significantly above average. Lower groups cost less to insure; UK fleet average is around Group 22.

Source: ABI Group Rating Panel · administered by Thatcham Research · groups cover standard variants; performance trims may sit higher. Browse all insurance groups →

28–46

out of 50

Compare quotes →

Top ten reasons for rejection.

Filter failures:

  1. 01

    Windscreen or window damaged or seriously discoloured but not adversely affecting driver's view

    40 occurrences · 2.0% of tests

  2. 02

    Brake pipe damaged or excessively corroded

    32 occurrences · 1.6% of tests

  3. 03

    Tyre tread depth not in accordance with the requirements

    21 occurrences · 1.1% of tests

  4. 04

    Engine MIL illuminated indicating a malfunction

    21 occurrences · 1.1% of tests

  5. 05

    Parking brake efficiency below minimum requirement

    19 occurrences · 1.0% of tests

  6. 06

    A tyre cords visible or damaged

    18 occurrences · 0.9% of tests

  7. 07

    Lamp emitted colour, position or intensity not in accordance with the requirements

    18 occurrences · 0.9% of tests

  8. 08

    Wiper blade defective

    17 occurrences · 0.9% of tests

  9. 09

    A rear registration plate lamp or light source missing or inoperative in the case of multiple lamps or light sources

    16 occurrences · 0.8% of tests

  10. 10

    A suspension pin, bush or joint excessively worn

    14 occurrences · 0.7% of tests

Counts cover Major and Dangerous defects logged at test. Advisory items excluded so this shows why a car was rejected, not just what the tester flagged in passing.

Worst-case fix budget · top 2 failures

£100–£185

If every one of this Unclassified's most-logged Major fails hit at the same MOT, that's the real-world UK garage range. Reality is usually one or two items, not all of them. Open the estimator →

Try the calculator

Build your own retest budget.

Year-band analysis

Best year to buy. Worst to avoid.

First-time MOT pass rate split by registration band. A 16.1-point gap between bands means the year you buy Mercedes Benz Unclassified has a real effect on what turns up at the garage.

Best band to buy

96.5%

2021+ registration

the 2021-on band climbs to 96.5% — a 16.1-point improvement. Tests in this band average 19,276 miles — roughly 60K miles fewer on the clock than the older band. Failures here are mostly wear items: not working, does not clear the windscreen effectively — the structural issues that drag down older examples don't appear in the top-10 for this band. Post-2020 examples are early in their MOT life and generally show the cleanest records.

Band to be cautious about

80.4%

Pre-2018 registration

On the older band (pre-2018), the data shows a 80.4% pass rate against a fleet average of 96.5% on the newer band. The main culprits logged at test: damaged but not adversely affecting driver's view, tread depth below requirements of 1.6mm, and incorrect colour. Average mileage on test for this band is 79,596 miles — high-mileage wear items are a recurring theme.

Best band to buy: 2021+ (96.5% first-time pass). Worst band to avoid: pre-2018 (80.4% pass). That's a 16.1-point spread across 1,470 older tests and 145 newer ones — year of build makes a material difference on this model.

Year-spread leaderboard →

Tools that pre-empt a retest.

Picked against this car's top failure patterns. Affiliate links to Amazon UK — we earn a small cut at no cost to you. Disclosed up-front, doesn't shape the data.

Item 01 · Amazon UK

Digital tyre-tread depth gauge

Five quid for a gauge beats £150 for a retest. UK MOT minimum is 1.6mm — most testers fail anything below 2mm to be safe.

Search Amazon UK

My Motor World · affiliate

Parts & supplies for this fix

Affiliate links — small commission, no extra cost to you.

Denso W14E Spark Plug (Single)

Denso

Denso W14E Spark Plug (Single)

£1.09

View at My Motor World →

Denso W16EX-U Spark Plug (Single)

Denso

Denso W16EX-U Spark Plug (Single)

£1.09

View at My Motor World →

Denso W16FSR Spark Plug (Single)

Denso

Denso W16FSR Spark Plug (Single)

£1.09

View at My Motor World →

Denso W9LM-US Spark Plug (Single)

Denso

Denso W9LM-US Spark Plug (Single)

£1.09

View at My Motor World →

Click Mechanic · affiliate

Book a mobile mechanic

Affiliate links — small commission, no extra cost to you.

Mobile mechanic · UK-wide

Book a mechanic at your door.

Fixed-price quotes upfront. No garage needed. Click Mechanic sends a vetted local mechanic to you — home, work, or roadside.

Get a quote →

Buying or keeping an Unclassified?

Use the failure ranking as a pre-test checklist or a haggling lever. Treat the headline pass rate as a fleet-wide trend, not a guarantee on any individual car.

If you own an Unclassified and your last MOT looked nothing like the ranked failures above, that's normal — individual cars vary widely. The ranking shows the patterns testers flag most often across the country.