MOT fail rates by first-use year

2009 Mercedes-Benz B-Class MOT fail rate and common faults

How Mercedes-Benz B-Class cars first used in 2009 did at their MOTs from 2022 to 2025, against all cars of the same age. From 18,323 DVSA MOT tests of these cars. First use is usually the date the car was first registered.

MOT data updated 28 September 2026

At 16 years, tested in 2025

MOT fail rate at age 16 (n=4,061)41.4%

All cars at 16 years (n=4,858,625)42.6%

Difference−1.2 pts

MOT tests of 2009 cars, 2022 to 202518,323

What stands out

In 2025, at 16 years old, Mercedes-Benz B-Class cars first used in 2009 failed 41.4% of MOTs (4,061 tests), 1.2 points below the 42.6% for all cars that age.
From 2022 to 2025, as these cars went from 13 to 16 years old, the fail rate moved from 38.0% to 41.4%.
Mercedes-Benz B-Class cars first used a year earlier, in 2008, failed 45.2% at the same age of 16 years (3,563 tests, in 2024).
The most common fail item that is not a wear item, for the Mercedes-Benz B-Class at 16 years, is driveshaft CV boot split, at 8.1 per 100 MOTs (all cars: 2.9).

MOT fail rate by test year

Mercedes-Benz B-Class cars first used in 2009: share of MOT tests that failed, by test year, against all cars of the same age. Years with fewer than 1,000 tests are not shown.
Test year	Age	MOT fail rate	Tests (n)	All cars	Difference
2022	13 years	38.0%	5,026	38.3%	−0.2 pts
2023	14 years	40.9%	4,819	40.3%	+0.6 pts
2024	15 years	43.1%	4,417	41.6%	+1.5 pts
2025	16 years	41.4%	4,061	42.6%	−1.2 pts

Most common faults at 16 years

These figures cover all Mercedes-Benz B-Class MOTs at 16 years: cars first used 2006 to 2009, tested 2022 to 2025 (n=13,766). The list uses every first-use year so it has enough tests. Wear items (tyres, brake pads, wipers, bulbs) say more about upkeep than about the design.

MOT fail items

Fail item	Per 100 MOTs	All cars
Driveshaft CV boot split	8.1	2.9
Coil spring broken	6.4	3.9
Suspension ball joint worn	5.2	2.5
Rigid brake pipes: excessively corroded	4.0	1.6
Washers: provides insufficient washer liquid Wear	3.9	2.3
Brake light not working Wear	3.7	4.0
Handbrake too weak	3.4	2.5
Dipped headlight not working Wear	3.1	2.4
Side/position light not working Wear	2.7	5.9
Brake pads under 1.5 mm Wear	2.6	2.0

Per 100 of the MOTs above (n=13,766). A test with two items counts once for each.

Advisories

Advisory	Per 100 MOTs	All cars
Rigid brake pipes: corroded, covered in grease or other material	21.5	8.8
Tyre tread close to the legal limit or worn on the edge Wear	15.8	18.2
Brake discs: worn, pitted or scored, but not seriously weakened	14.3	11.2
Tyre condition: slightly damaged/cracking or perishing Wear	11.4	9.5
Drive shaft joints: constant velocity boot severely deteriorated	10.3	3.5
Brake pads wearing thin Wear	8.3	6.8
Coil spring: corroded	6.5	7.4
Shock absorber misting oil	5.7	4.1
Non-component advisories: Play in steering rack inner joint(s)	4.9	3.0
Flexible brake hoses: slightly deteriorated	4.7	1.2

Per 100 of the MOTs above (n=13,766). A test with two items counts once for each.

Fuel type at 16 years

These figures cover all Mercedes-Benz B-Class MOTs at 16 years: cars first used 2006 to 2009, tested 2022 to 2025 (n=13,766). Each fuel is set against all cars of the same fuel and age. Fuels with fewer than 1,000 tests are not shown.

Fuel	Share of tests	MOT fail rate	Tests (n)	All cars, same fuel	Median mileage
Petrol	50.4%	41.4%	6,937	42.6%	89,412 miles
Diesel	49.6%	45.4%	6,829	42.8%	106,133 miles

Fail rate by mileage at 16 years

These figures cover all Mercedes-Benz B-Class MOTs at 16 years: cars first used 2006 to 2009, tested 2022 to 2025 (n=13,766). At 16 years, Mercedes-Benz B-Class cars at 120,000 to 150,000 miles failed more often (48.1%, n=2,468) than those at 30,000 to 60,000 miles (31.2%, n=1,444). Bands with fewer than 1,000 tests are not shown.

Mileage at test	MOT fail rate	Tests (n)	All cars
30,000 to 60,000 miles	31.2%	1,444	32.1%
60,000 to 90,000 miles	41.7%	4,007	41.4%
90,000 to 120,000 miles	46.3%	4,639	45.9%
120,000 to 150,000 miles	48.1%	2,468	46.8%

Car tax rules for a 2009 car

Cars first registered from 1 March 2001 to 31 March 2017 are taxed by CO2 emissions band, from band A (the lowest emissions) to band M. The band is set by the CO2 figure on the V5C logbook.

These are the rules, not the amount for a specific car. Car tax check

ULEZ and clean air zones

Petrol cars first registered from 2006 usually meet Euro 4, the petrol standard for the London ULEZ, so they usually do not pay the daily charge.
Diesel cars first registered before September 2015 usually do not meet Euro 6, so a 2009 diesel usually pays the ULEZ daily charge. A few models met Euro 6 early.
The clean air zones in Birmingham and Bristol use the same Euro 4 petrol and Euro 6 diesel standards. The low emission zones in Scotland use them too, but enforce them with fines, not a daily charge.

The Euro standard of the car decides, not the year alone. ULEZ checker

Other years of the Mercedes-Benz B-Class

2008 Mercedes-Benz B-Class 2010 Mercedes-Benz B-Class

Other Mercedes-Benz models first used in 2009

Model	Age at test	MOT fail rate	Tests (n)	All cars
Mercedes-Benz C-Class (2009)	16 years in 2025	35.2%	12,773	42.6%
Mercedes-Benz A-Class (2009)	16 years in 2025	40.2%	6,530	42.6%
Mercedes-Benz E-Class (2009)	16 years in 2025	29.7%	6,123	42.6%
Mercedes-Benz CLC (2009)	16 years in 2025	44.7%	3,062	42.6%
Mercedes-Benz CLK (2009)	16 years in 2025	39.2%	2,763	42.6%
Mercedes-Benz SLK (2009)	16 years in 2025	30.6%	2,461	42.6%
Mercedes-Benz M-Class (2009)	16 years in 2025	32.6%	1,808	42.6%
Mercedes-Benz CLS (2009)	15 years in 2024	36.3%	1,129	41.6%

More on the Mercedes-Benz B-Class

Read this with care. A fail rate is not a measure of build quality. How far cars are driven, how they are used and how well owners maintain them all change it, and wear items such as tyres and brake pads are common fails. Compare a model only with cars of the same age. Methodology and limits.

Found one you might buy? Vet the specific car.

These figures describe 2009 Mercedes-Benz B-Class cars as a group, not any one car. The VetTheCar Buying Report looks at the car you are buying: its MOT history, what similar cars did next, and what to ask the seller.

See an example Buying Report All car tools

Source

Contains public sector information licensed under the Open Government Licence v3.0. Source: DVSA anonymised MOT test data, class 4 normal MOT tests, 2022 to 2025. MOT data updated 28 September 2026.

Not affiliated with or endorsed by DVSA. How we calculate these figures · Data sources

Car tax and clean air zone rules are summarised from GOV.UK and Transport for London guidance. They are general rules and are not drawn from the MOT data.