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Mercedes-Benz A-Class MOT pass rate and common problems

85.3% of 629,532 Mercedes-Benz A-Class MOT tests pass.

The A-Class has a pass rate of 85.3%, a little higher than the average across all Mercedes-Benz models (83.5%).

The Mercedes-Benz A-Class passes its MOT 85.3% of the time — well above the national average for cars, which sits at 79.2%.

Own this Mercedes-Benz A-Class?

This is the average across every Mercedes-Benz A-Class in the dataset. Look up your own registration for its actual MOT history, and a free place to keep its maintenance records.

Have service invoices? Upload and keep them with your car’s history →

How to check and keep your Mercedes-Benz’s service history →

Pass rate by vehicle age

Pass rate drops sharply with age: the Mercedes-Benz A-Class tested at 0–3 years pass 93.6% of the time, compared with just 66.2% at 15+ years.

Pass rate by vehicle age band0–3 years93.6%3–6 years91.1%6–10 years84.3%10–15 years76.8%15+ years66.2%
Mercedes-Benz A-Class pass rate and average mileage by vehicle age band
Vehicle agePass rateTestsAverage mileage
0–3 years93.6%43,00526,046 miles
3–6 years91.1%231,65938,607 miles
6–10 years84.3%235,01666,407 miles
10–15 years76.8%79,85285,078 miles
15+ years66.2%40,00087,864 miles

Common MOT failure reasons for the Mercedes-Benz A-Class

The most common reason the Mercedes-Benz A-Class fails its MOT is tyres — present in 35.5% of failed tests, most often logged as "Tread depth below requirements of 1.6mm".

Top MOT failure categories for the Mercedes-Benz A-Class
CategoryShare of failed testsExample
Tyres35.5%Tread depth below requirements of 1.6mm
Lamps, reflectors and electrical equipment29.7%Not working
Brakes24.1%Less than 1.5 mm thick
Suspension23.2%Fractured or broken
Visibility15.7%Provides insufficient washer liquid
Noise, emissions and leaks8.5%Inoperative or indicates a malfunction
Seat belts and supplementary restraint systems6.1%Warning lamp indicates a fault
Body, chassis, structure5.0%Constant velocity boot split or insecure, no longer prevents the ingress of dirt
Road Wheels2.7%Fixing missing
Identification of the vehicle2.6%Does not conform to the specified requirements

Buying a used Mercedes-Benz A-Class: what to check

These checks follow the Mercedes-Benz A-Class’s own MOT record: the areas it fails on most often, and how that changes as the car gets older. None of them replaces a mechanic’s inspection, but they tell you where to look first.

The biggest drop in pass rate for the Mercedes-Benz A-Class comes between 10–15 years and 15+ years old, from 76.8% to 66.2%. If you are looking at one in or just past that range, read its MOT history closely.

By mileage, the steepest fall is from 30,000–60,000 mi to 60,000–90,000 mi: 88.0% down to 81.2%. Mileage matters as well as age, so compare the car’s recorded mileages with its year.

  1. 1. Tyres

    Recorded in 35.5% of failed Mercedes-Benz A-Class MOTs.

    Check tread depth across the whole width of every tyre, including the inner edge. Uneven wear can point to alignment or suspension problems. Look for cuts and bulges in the sidewalls.

  2. 2. Lights and electrics

    Recorded in 29.7% of failed Mercedes-Benz A-Class MOTs. 23.8% of tests at 15+ years failed on lights and electrics, against 1.5% at 0–3 years.

    Walk round with the lights on: headlights (dipped and main), indicators, brake lights, fog light and number-plate lamp. Check the dashboard warning lights come on with the ignition, then go out once the engine starts.

  3. 3. Brakes

    Recorded in 24.1% of failed Mercedes-Benz A-Class MOTs. 19.1% of tests at 15+ years failed on brakes, against 0.6% at 0–3 years.

    On the test drive, the car should stop straight without pulling or juddering, and the handbrake should hold it on a slope. Look through the wheels for scored or heavily lipped discs.

  4. 4. Suspension

    Recorded in 23.2% of failed Mercedes-Benz A-Class MOTs. Rare on young cars, but 15.9% of tests at 15+ years failed on suspension.

    Listen for knocks over bumps and speed humps, and check the car sits level. Push down on each corner: it should settle rather than keep bouncing.

  5. 5. Windscreen and wipers

    Recorded in 15.7% of failed Mercedes-Benz A-Class MOTs. 9.7% of tests at 15+ years failed on windscreen and wipers, against 1.4% at 0–3 years.

    Look for windscreen chips and cracks in the driver’s line of sight, and check the wipers clear the screen and the washers work.

Check the car’s own MOT history. Averages describe the model, not the car in front of you. Look up its registration for past failures, advisories that were never fixed, and gaps or dips in the recorded mileage.

Ask for the service history. Invoices show what was done and when; a stamp alone shows less. See how to check Mercedes-Benz service history and what a service history check can tell you.

Related Mercedes-Benz models

Frequently asked questions

What is the MOT pass rate for the Mercedes-Benz A-Class?
85.3% of Mercedes-Benz A-Class MOT tests pass, based on 629,532 tests in the DVSA anonymised MOT tests and results dataset.
What are the most common MOT failures for the Mercedes-Benz A-Class?
The most common reason the Mercedes-Benz A-Class fails its MOT is tyres — present in 35.5% of failed tests, most often logged as "Tread depth below requirements of 1.6mm".
What are the common problems with the Mercedes-Benz A-Class?
Going by its MOT results, the most common problem areas on the Mercedes-Benz A-Class are tyres; lights and electrics; brakes.
What should I check when buying a used Mercedes-Benz A-Class?
Start with the areas it most often fails its MOT on: tyres; lights and electrics; brakes; suspension; windscreen and wipers. Then check the specific car's MOT history by registration for failures, advisories and mileage, and ask the seller for service invoices.
Does this show the Mercedes-Benz A-Class's service history?
No — this is MOT test data, which covers roadworthiness, not servicing. A service history is a separate record of maintenance work, which a specific car only has if its owner has kept it. See the Mercedes-Benz service history guide for how to check and keep one.