Know Your MOT
31.0%fail rate

Merc Slk230 MOT failure rate

What a Merc Slk230 fails its MOT on, from real DVSA test data, and the part that resolves each item.

Based on 29 MOT tests in DVSA data.

We hold 29 MOT tests for the Merc Slk230 in the DVSA data. That is a smaller sample than our high-volume models, so treat these figures as indicative rather than definitive.

On what we have, about 31.0% fail, most often on lamps & electrical, suspension, tyres, brakes. For a precise picture of your own car, use the registration check on the home page. Confirm any part against your registration or VIN before buying.

What it fails on, and why

Lamps & electrical33.3% of failures

Lighting is the single most common MOT failure and the cheapest to put right. A blown headlight, brake-light or number-plate bulb, a cracked lens, or a headlamp beam that points too high or low will all fail. Most are a two-minute bulb swap.

Suspension22.2% of failures

Suspension failures usually mean a worn or snapped coil spring, a leaking shock absorber, or play in a lower arm ball joint or bush. The tester checks for corrosion, fractures and excessive movement. A broken front spring is one of the most common failures on higher-mileage cars and is a straightforward replacement.

Tyres22.2% of failures

Tyres fail for tread below the 1.6mm legal limit across the central three-quarters, uneven or exposed-cord wear, or sidewall damage. The tester inspects all four; a single illegal tyre is a fail.

Brakes22.2% of failures

Brake failures cover worn pads and discs, an imbalance between wheels, corroded or scored discs, or a binding caliper. Braking efficiency is measured on a rolling road, so a spongy or pulling brake shows up as a low reading.

Visibility/wipers11.1% of failures

Visibility failures include torn or smearing wiper blades, a washer jet that does not reach the screen, and chips or cracks in the driver's swept area. Blades and washer fluid are quick, cheap fixes.

Other11.1% of failures

This covers a range of smaller items, from a non-working horn to a warning light left on.

The parts that fix each

If your car has just failed, you have 10 working days to fix the items and get a free partial retest. These are the usual parts; confirm the exact fitment against your registration or VIN before buying.

For the lamps & electrical failure: Merc Slk230 headlight and indicator bulbsSearch Amazon for Merc Slk230 headlight and indicator bulbsaffiliate searchFind Merc Slk230 headlight and indicator bulbs on eBayaffiliate
For the suspension failure: Merc Slk230 suspension springs and shock absorbersSearch Amazon for Merc Slk230 suspension springs and shock absorbersaffiliate searchFind Merc Slk230 suspension springs and shock absorbers on eBayaffiliate
For the tyres failure: Merc Slk230 tyresSearch Amazon for Merc Slk230 tyresaffiliate searchFind Merc Slk230 tyres on eBayaffiliate
For the brakes failure: Merc Slk230 brake pads and discsSearch Amazon for Merc Slk230 brake pads and discsaffiliate searchFind Merc Slk230 brake pads and discs on eBayaffiliate
For the visibility/wipers failure: Merc Slk230 wiper bladesSearch Amazon for Merc Slk230 wiper bladesaffiliate searchFind Merc Slk230 wiper blades on eBayaffiliate

Other models

Merc Sprinter MOT failures15.4% failure rateMerc Econic MOT failures0.0% failure rateMerc Atego MOT failures12.1% failure rateFord Fiesta MOT failures27.1% failure rate

Sources: DVSA MOT History API: MOT test results and defect data ยท DVSA MOT testing data for Great Britain