MOT failures by make

Mercedes-Benz MOT faults: which failures are more common than on similar cars

Across 3,425,149 MOT tests of Mercedes-Benz cars in 2023–2024, 5 of the make's most common failure items stand out against cars of the same age, mileage and fuel, led by “Rigid brake pipes: excessively corroded” at 1.71× the comparable rate. Overall Mercedes-Benzs passed 76.7% of tests and failed 0.86× as often as comparable cars.

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Data to 2024-12-30 · Page updated 2026-09-28 · Publisher: 73 Auto

Mercedes-Benz MOT tests: 3,425,149; 1,772,906 cars, 2023–2024
Initial pass rate: 76.7%; DVSA results, retests excluded
Faults that stand out: 5; passed the make × item gate

Failures more common on Mercedes-Benzs than on similar cars

Each links to the model-by-model and age breakdown for Mercedes-Benz.

Rigid brake pipes: excessively corroded · 1.71× · 1.05% of tests
Ball joint: ball joint excessively worn · 1.67× · 2.13% of tests

Failures less common on Mercedes-Benzs

Common failure items where Mercedes-Benzs do clearly better than comparable cars, beyond the make's overall level.

Position lamp: not working · 0.41× · 0.93% of tests
Stop lamp: not working · 0.52× · 0.87% of tests
Wipers: does not clear the windscreen effectively · 0.53× · 1.08% of tests

Mercedes-Benz’s most common MOT failure items

Ranked by how many Mercedes-Benz tests failed on each item. The last column compares with cars of the same age, mileage and fuel (1.00 = the same rate).

Mercedes-Benz: most common MOT failure items with observed ÷ expected
Defect item	Rank	Tests failing	Share	vs similar cars
Tread depth: tread depth below requirements of 1.6mm	#1	85,471	2.50%	1.03×
Coil spring: fractured or broken	#2	79,488	2.32%	1.09×
Ball joint: ball joint excessively worn	#3	72,930	2.13%	1.67×
Condition: has ply or cords exposed	#4	56,874	1.66%	1.21×
Condition: has a cut in excess of the requirements deep enough to reach the ply or cords	#5	54,029	1.58%	1.17×
Brake pads: less than 1.5 mm thick	#6	46,022	1.34%	0.68×
Washers: provides insufficient washer liquid	#7	38,940	1.14%	0.84×
Wipers: does not clear the windscreen effectively	#8	36,875	1.08%	0.53×
Rigid brake pipes: excessively corroded	#9	35,846	1.05%	1.71×
Rbt (sp): efficiency below requirements	#11	34,317	1.00%	0.98×
Malfunction indicator lamp: inoperative or indicates a malfunction	#12	34,300	1.00%	1.33×
Position lamp: not working	#13	31,705	0.93%	0.41×
Headlamp aim: too low	#14	31,310	0.91%	0.81×
Stop lamp: not working	#15	29,951	0.87%	0.52×
Linkage ball joint dust cover: ball joint dust cover no longer prevents the ingress of dirt	#16	28,962	0.85%	1.40×

Only the 150 most common national MOT failure items are compared; a rank counts every failure item recorded on the make.

How to use this

The list shows what a Mercedes-Benz is more likely than other cars to fail on, which is where to look on a pre-MOT check or a used-car inspection. The model pages break the same data down further — see Mercedes-Benz MOT pass rates by model.

Limitations

Official data: DVSA anonymised MOT results (2023–2024). 73 Auto analysis: expected failures apply the national rate of each item for the test's age, mileage band and fuel. MOT results reflect maintenance and use as well as design; they do not rank makes by reliability.

Check a Mercedes-Benz’s MOT history before you buy

Enter a registration to see which of these faults that particular car has failed or been advised on, and what it costs to run. Your first check is free and shows the vehicle summary and its headline ownership cost. The category-by-category breakdown is part of a paid check.

UK number plate or 17-character VIN

Where these figures come from

Anonymised MOT tests and results (2023 and 2024) — Driver and Vehicle Standards Agency (DVSA). Open Government Licence v3.0.

Figures labelled as 73 Auto estimates are our own analysis of these sources, set out in the methodology and data sources. To report a factual error, see corrections.