MOT failure rates

Smart #5 MOT failure rates: what to expect

What fails on a Smart #5 at MOT, how often, and what each fix typically costs.

Updated 4th September 2026

The Smart #5 has a few common issues that can lead to an MOT failure. The most frequent problems include lighting and signalling faults, suspension issues, and brake system deficiencies. Fixing these issues can vary in cost, but addressing them promptly can help ensure your vehicle passes its MOT.

Lighting and Signalling Failures

Lighting and signalling issues are among the most common reasons for MOT failures on the Smart #5. This can include problems with headlights, brake lights, indicators, and fog lights. A blown bulb or faulty wiring can lead to a failure, as proper visibility and signalling are crucial for safety.

Regularly checking your lights before the MOT can help avoid these issues.

Suspension Problems

Suspension issues can significantly impact the Smart #5’s handling and ride comfort. Common problems include worn shock absorbers, damaged springs, and issues with the suspension bushes. These components are essential for maintaining vehicle stability and ensuring a smooth ride.

If multiple components are affected, the total cost can escalate. Regular maintenance and inspections can help identify suspension issues early, ensuring a smoother MOT experience.

Brake System Deficiencies

The brake system is critical for safety, and deficiencies in this area are a common cause of MOT failures for the Smart #5. Issues may include worn brake pads, damaged discs, or leaks in the brake lines. A well-functioning brake system is essential for effective stopping power.

Regularly checking brake components can help prevent costly repairs and ensure safety.

Tyre Condition and Tread Depth

Tyres are vital for vehicle safety and performance, making them a common failure point during the MOT for the Smart #5. Issues include insufficient tread depth, uneven wear, or damage to the sidewalls. The legal minimum tread depth in the UK is 1.6mm, and anything below this can lead to an MOT failure.

Regularly inspecting your tyres can help avoid these issues and ensure compliance with safety standards.

Exhaust Emissions and System Failures

Exhaust emissions are a critical aspect of the MOT, and failures in this area can occur due to a faulty catalytic converter, exhaust leaks, or issues with the engine management system. The Smart #5 must meet specific emissions standards, and any failure to do so can result in an MOT failure.

Regular servicing and checks can help keep emissions in check and prevent costly repairs.

Bodywork and Structural Integrity

Although less common, issues with bodywork and structural integrity can lead to MOT failures for the Smart #5. Problems may include rust, corrosion, or damage to the chassis. These issues can compromise safety and are taken seriously during the MOT inspection.

Keeping your vehicle clean and addressing minor rust spots early can help maintain its structural integrity and avoid costly repairs.

Smart #5 recall record

1 recall has been issued for the Smart #5, in 2026.

  1. Vehicle Total upgrade via sVDS 2.0

    R/2026/276

    Issued 31 July 2026

    It has come to our attention that your vehicle is part of a very small number of smart #5 vehicles of which under very specific circumstances the braking software may underperform and lead to unexpected skidding on specific surfaces in icy or wet weather conditions. Test results have shown that this scenario can occur on low friction surfaces (e.g. epoxy or tilted floors). The issue could not be reproduced on normal road surfaces. Should these specific circumstances occur it cannot be ruled out that the braking leads to skidding and loss of control of the vehicle.

    Remedy:The corrective measure consisting of the release of a new braking software that will correct the deviated behaviour.

    Affects cars built Nov 2025 to May 2026

A recall applies to a build range, not to every car of this model. Check a registration to see whether one specific vehicle has an outstanding recall.

Frequently asked questions

What is a Smart #5 mot?

The Smart #5 mot refers to the Ministry of Transport test for Smart vehicles, ensuring they meet safety and environmental standards. It is a legal requirement for vehicles over three years old in the UK.

How often do I need to get my Smart #5 mot?

You need to have your Smart vehicle tested annually once it reaches three years old. It's important to keep track of the expiry date to avoid penalties.

What happens if my Smart #5 mot fails?

If your Smart vehicle fails the mot, you will receive a list of issues that need to be addressed. You must fix these problems and have the vehicle retested before you can legally drive it.

Can I drive my Smart vehicle if the mot has expired?

No, you cannot legally drive your Smart vehicle if the mot has expired, unless you are driving it to a pre-booked mot appointment. Doing so can result in fines and penalties.

How can I prepare my Smart vehicle for the mot?

To prepare for the mot, check the lights, brakes, tyres, and fluid levels. It’s also a good idea to ensure that your vehicle is clean and free from any obvious defects.

Where can I get my Smart #5 mot done?

You can get your Smart #5 mot done at any authorised mot testing centre in the UK. Many garages and dealerships offer this service, so you can choose one that is convenient for you.

What documents do I need for the Smart #5 mot?

You should bring your vehicle registration document and any previous mot certificates. Having your insurance details handy can also be helpful.

Is there a grace period for getting a Smart #5 mot?

There is no official grace period for getting an mot. It is best to book your test before the expiry date to ensure you remain compliant with UK law.

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