EV MOT failure through tyre wear a cause for concern, warns IMI

The Institute of the Motor Industry (IMI) has warned that tyres present the greatest risk to road safety, especially on electric vehicles (EVs), if there is any extension to the first MOT date.

EV MOT failure rates represent a serious issue, as the UK government is pushing the new automotive market down this route. This means they will be the primary vehicles to move under the proposed 4-1-1 MOT scheme, even though they are harder on their wear-and-tear items. 

As part of its detailed response to the MOT consultation, which closes on 22nd March, the IMI has worked with Garage Industry Trends to examine root causes in current patterns of MOT failure, including the EV MOT failure rate linked to tyres. The IMI analysis provides clear evidence that extending the date for the first MOT will significantly increase road user risk. 

The risks surrounding electric vehicles, which are heavier than ICE vehicles and cause heavier wear to their tyres, will be heightened if the first MOT date is extended. Evidence drawn from MOT testing records supplied to the IMI by the Department for Transport shows that comparative to petrol engine vehicles, EV MOT failure rates are much higher for their first test.

EV MOT failure causes headache for proposed schedule

EV MOT failure rates for 2018 registered vehicles (all classes) was 11.51%. This is lower than diesel (15.98%) but higher than petrol (10.89%). This pattern holds for 2017 and 2016 registration years. Given that a large proportion of EV owners in 2018 can be classed as enthusiast (early adopters) and would likely maintain their car better than today’s average EV driver, the IMI believes this is a significant finding.

The data also indicates that EV MOT failure rate is comprised of more dangerous items than petrol vehicles, primarily being tyres. The data from the Department for Transport shows that looking at the class 4 car parc from 2015 – which would have had their first MOT in 2018 – electric vehicles are 1.95% more likely to fail an MOT test on tyres than petrol vehicles. This is a relative difference of 46%, with Tesla having the highest likelihood of any car make to fail on tyres. 46% of all failure items for electric vehicles are related to tyres, compared to 32% for petrol vehicles.

Tyres are a tricky subject when it comes to EVs. The cars themselves are heavier, which leads to more wear on the tyre. This creates a problem with tyre particulates, small particles of rubber that could find their way into the water table. Tyre manufacturers are developing and selling special EV tyres that can handle the higher weights, but if incorrect tyres are fitted, these would wear faster, leading to a higher EV MOT failure rate.

The argument from the government is that cars are becoming more reliable, and therefore delaying the first MOT by a year helps reduce unnecessary motoring costs. Yet the EV MOT failure rate linked to tyres shows that drivers are not checking wear-and-tear items that are not linked to vehicle reliability, but are linked to safety.

“This is not about the quality of tyres on cars,” explained Hayley Pells, Policy Manager at the IMI. “It is all about the lack of awareness amongst the general driving public about the importance of routine checking of vehicle condition and tyres in particular.

“Many motorists are likely to believe that they can wait for their first MOT to pick up any issues with tyres. However, the data shows that electric vehicles tend to fail on their tyres more than traditional petrol vehicles. If the first MOT is extended this will be a serious concern for road safety as well as potentially having a significant impact on consumer confidence in electric vehicles, which is unfair as the technology appears to perform well in other areas of current MOT testing.

“With the majority of first MOT tests taking place coupled with routine maintenance it is shocking that these figures exist for EV MOT failure rates at all, suggesting that many of these vehicles have not been subject to routine maintenance that would pick these items prior to MOT test,” continued Pells. “The IMI’s response to the MOT Consultation will therefore strongly advise that increasing the time before a periodic inspection of cars is detrimental for road safety. It reduces the frequency of maintenance and inspections that are critical to ensuring that vehicles are in good condition and performing at their best.”

Figure 1 Tyre analysis for MOT test data compared by powertrain (Garage Industry Trends)

“Clearly the road safety risk has to be the first point of focus for the MOT Consultation,” concluded Pells. “However, the IMI firmly believes there will also be a significant impact on the ability of the automotive aftermarket to be properly skilled for the growing electric vehicle parc if the date of the first MOT was extended. Reduced income despite the DVSA expecting MOT testing centres to invest in new equipment and professional training could see reduced choice for the motorist.  Plus, the increased need for greater services from the DVSA to the MOT test centres for the new electric powertrain, despite a shortfall of income from motorists to run the service if the date for the first MOT is extended, could have the unintended consequence of requiring an unaccounted sum of public money.”

Related Posts