What Wears Out

Smart · fully electric · 2,590 inspections in 2024

Smart EQ what wears out, measured

8.3%

fail their MOT first time. Ranks 30 of 83 electric cars tested; fleet average for electric cars is 12.0%.

At three years old the Smart EQ fails 6.8% of the time, under the 8.2% of a petrol car the same age. By 4 years that reaches 10.3%. Tyres cause 44.0% of its failures.

2,293passed
216failed
81passed after repair
3.5 yrsaverage age tested

Data sheet

Inspections analysed
2,590 first-time tests, retests excluded
First-time failure rate
8.3% (electric average 12.0%, petrol 8.2%, diesel 14.5%)
Best year
3 years old, 6.8% fail
Worst year
4 years old, 10.3% fail
Biggest cause of failure
Tyres, 44.0% of all defects
Most unusual for its class
Visibility: 2.7× the share seen on petrol and diesel cars

Versions seen in the tests

Exactly as recorded on the certificate. Counts are inspections, not cars.

  • EQ FORTWO PRIME EXCLUSIVE388
  • EQ FORFOUR PREMIUM345
  • EQ FORFOUR PRIME EXCLUSIVE334
  • EQ FORFOUR PULSE PREMIUM326
  • EQ FORTWO PULSE PREMIUM299
  • EQ FORFOUR EXCLUSIVE197
  • EQ FORTWO EXCLUSIVE189
  • EQ FORTWO PREMIUM172

Failure rate by age

The line to watch is the red one. Dashed lines are petrol and diesel cars of the same age, tested the same year.

    Points are hidden where fewer than 50 cars of that age were tested.

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    Where it holds up

    • Suspension fail less often than on petrol and diesel cars (2.8% of defects vs 13.6%)
    • Brakes fail less often than on petrol and diesel cars (10.8% of defects vs 18.7%)
    • Lighting fail less often than on petrol and diesel cars (6.4% of defects vs 16.5%)
    • Steering fail less often than on petrol and diesel cars (0.6% of defects vs 3.1%)

    Where it fails

    • Tyres take a bigger share of failures than on the wider fleet (44.0% vs 23.7%)
    • Visibility take a bigger share of failures than on the wider fleet (32.7% vs 11.9%)

    What fails, by system

    Share of all defects that caused a failure. The dark mark is the same system on petrol and diesel cars of the same age.

    SystemShare of failing defectsThis carvs fleet
    Tyres
    44.0% 1.9× more
    Suspension
    2.8% 4.9× less
    Brakes
    10.8% 1.7× less
    Visibility
    32.7% 2.7× more
    Lighting
    6.4% 2.6× less
    Steering
    0.6% 5.2× less
    Body
    0.6% 6.8× less

    Top defects on the certificate

    Wording from the DVSA inspection manual, so it matches what a tester writes.

    1. Wiper blade missing or obviously not clearing the windscreen101
    2. A tyre seriously damaged95
    3. A tyre cords visible or damaged27
    4. Tyre tread depth not in accordance with the requirements18
    5. Tyres on the same axle or on twin wheels are different sizes10
    6. a brake lining or pad worn below 1.5mm7

    Check before you buy

    • Trivial to fix, but a car advertised with worn wipers and a fresh failure certificate tells you how it was maintained.
    • Check tyre age and tread across the full width, inner edge included. Electric cars wear tyres faster; a cheap mismatched set on a used car tells you how it was run.
    • Ask when the brakes were last stripped and cleaned. Regenerative braking barely wears the pads, so discs and calipers corrode and seize instead.
    • Ask for the full MOT history by registration on the free DVSA service: advisories are next year's failures.

    What owners say about the same faults

    No owner discussion has been matched to this car's recorded defects yet. Reports are re-collected every quarter; the figures on this page do not depend on them.

    Summaries written by us, never quotes; every entry links to its source. Owner reports have no denominator and never feed the failure rate.

    Similar cars in the data

    Closest failure rate and age profile, different brand.

    Other Smart electric cars

    Three things the data shows

    • 2,590 inspections in 2024 make this one of the adequately-documented electric cars in the data.
    • Visibility take 2.7× the share of failures they take on petrol and diesel cars of the same age.
    • Failure rate rises from 6.8% at 3 years to 10.3% at 4: a gentle ageing curve.

    What the inspection does not tell you

    No battery health, no motor, no charging performance. The test covers brakes, suspension, steering, tyres, lights, visibility and structure. A car with a badly degraded battery passes as long as it stops and steers. Read this page as evidence about the chassis, not the powertrain.

    Cars are tested from their third year, so the newest model years are missing. Every figure carries its sample size for that reason. Full methodology.

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    Data: DVSA anonymised MOT tests, 2024 test year, OGL v3.0. Computed by What Wears Out editorial team. Last updated .