For the first time, the TÜV evaluates the HU results of the most popular electric cars in Germany - Smart EQ, Renault Zoe, BMW i3 but also Tesla Model S. The defect rates are sometimes above average, the affected assemblies are surprising.
When it comes to maintenance and repairs, electric cars should be cheaper than combustion engines. The reason: many assemblies that cause trouble in petrol or diesel engines do not exist in e-cars: exhaust systems and cleaning, turbochargers, there is no need to change the oil and the brakes wear out much less because e-cars decelerate a lot through recuperation.
E-car brakes: wear and tear due to non-use
However, the latter in particular can also lead to problems because the brakes in e-cars are used so rarely that the discs rust or the ability to operate them suffers. This can then be noticed during the main inspection. In the first notable number of main inspections, however, this only played a role in one of the three vehicle types examined - although the absolute numbers of e-cars examined are still low - the first main inspection is due three years after initial registration, calculated from the 2021 examination year the new registration years 2017 and 2018, when there was no talk of the e-car subsidy. ,
Because for the TÜV Report 2022, the association evaluated around 9.6 million main inspections of cars, which it carried out at its test centers from July 2020 to June 2021. The publication shows 222 vehicle models in 5 age groups. In the ranking of 2 to 3 year old cars alone, 128 vehicle models are listed. The four most popular e-cars now being considered are also not included in the TÜV report due to the small number of units.
First e-car HUs of the years 2017 and 2018
The results published at the end of January are based on 1142 main inspections of the BMW i3, 1939 of the Renault Zoe, 1645 of the Smart Fortwo Electric Drive and 812 of the Tesla Model S. "On this basis a preliminary assessment of the technical safety of the respective vehicle models is possible," says the TÜV.
In the 2 to 3-year-old vehicles with combustion engines, the proportion of cars with "significant defects" is 4.7 percent on average. Cars with significant defects fall through the main inspection and have to be presented again after the repair before they receive the general inspection sticker. ,
Smart EQ: The smallest has the fewest defects
Of the four electric vehicles considered, the electric Smart Fortwo performed best with a defect rate of 3.5 percent. In the list of 128 2- to 3-year-old combustion engines listed in the TÜV report, the E-Smart would end up in the first third. It is followed by the BMW i3, which hits the short cut with 4.7 percent and would rank in the second third.In addition to defective low beams, defects in the brake discs are often noticed in the i3 according to TÜV - for the reasons mentioned at the beginning. With the i3, BMW has set the recuperation so strongly as standard that the small car can be driven 90 percent of the time in the city without pressing the brake pedal ("One Pedal Driving"). dr Joachim Bühler, Managing Director of the TÜV Association, advises: "Owners of e-cars should apply the brakes whenever possible and service them regularly." ,
The Renault Zoe, sas e-car with the third lowest defect rate apparently has fewer problems with the brakes; in fact, the first models of the French small car recuperate less. The often best-selling e-car in recent years would end up in the bottom third of the overall statistics (with combustion engines) with a defect average of 5.7 percent. In addition to defective or incorrectly adjusted headlights, the Zoe has an above-average number of defects in the axle suspension. Possibly also a typical e-car problem: Unlike the i3, whose weight remains well below 1,400 kg thanks to the expensive carbon body, the slightly larger Zoe weighed a good 1,500 kg with the initially only 22 kWh battery and moves with the larger batteries after the facelift towards 1,600 kg.
Tesla with problems with the chassis
Tesla's Model S, on the other hand, has a battery that is up to around 5 times larger, which weighs around 700 kilograms, the vehicle weight of the almost 5 meter long sedan then increases to more than 2160 kg. In addition to defects in the fog light and the low beam, the Model S at the HU may be particularly concerned about problems with the wishbones. Overall, it performs worst in the e-car quartet considered by TÜV. With a defect rate of 10.7 percent, every tenth Tesla Model S fails the first general inspection and would also end up in the last third of the 128 one to three-year-old combustion engines. Only the Dacia Duster (11.4 percent fail the first HU) and the Dacia Logan (11.6 percent) would rank behind the Tesla. ,
It will be interesting to see how e-cars fare compared to combustion engines with increasing age - the group of cars older than 10 years is now the largest in Germany (42.1 percent) and the average age of the Passenger cars has risen continuously in recent years and is now 9.8 years. The defect rate naturally increases with age (from 4.7 to 22.8 percent in 2022). Will the types of defects noticed in the four e-cars then continue to dominate? In any case, problems with the lighting that are comparatively easy to fix are also the most common among the eight to nine-year-old group, while defects in axle suspension and brakes are only the third or fourth most common with combustion engines, while Zoe and Tesla are more often than average at a young age Running gear problems were noticed.Interestingly, an early electric car does not appear here because it initially had problems with the suspension: With the EQC, Mercedes first had to strengthen the axle bolts before the electric SUV based on the GLC picked up speed in terms of quantities. Incidentally, the GLC with a combustion engine is the reliability winner in the TÜV report for one to three-year-olds: only 1.5 percent defect rate.
The second most common "ageing problem" of combustion engines, on the other hand, is unlikely to occur with e-cars: In the 2022 report, that was oil loss in the engine or transmission. ,
Fewer parts, fewer repairs and maintenance requirements - this applies to e-cars in the workshop. A more differentiated picture emerges from the TÜV. Specific strengths and weaknesses emerge on the basis of a small data basis: Oil loss is unlikely to drive up the defect rate of electric cars in the future either, while problems with suspension and brakes could remain an issue. There is potential for improvement in terms of design for both: the manufacturers obviously have to make the chassis of the comparatively heavy Stromer stronger, as Mercedes did with the bumpy start of series production of the EQC, which weighs around 2.5 tons. And the brakes could be automatically applied per trip - in this case instead of recuperation. Then at least the brake discs would not rust away unused without the driver having to think about it.