Modern advancements in electric and hybrid vehicles have recently faced criticism for suggesting drivers can reach speeds of 80mph in 30mph zones, even in areas near schools.

The Traffic Sign Recognition (TSR) system utilizes specialized cameras to read road signs and provides drivers with both audio and visual notifications regarding current conditions, including speed limits.

Nevertheless, numerous online discussions reveal that vehicle owners are frustrated with the system’s inaccuracies. This feature, now standard in high-end models like the £55,000 Mazda CX-60 and £37,000 Volvo XC40, reportedly misinterprets signs, triggering alerts for non-existent UK speed zones of 80mph, 90mph, and even 100mph.

One driver experienced a suggestion to drive at 80mph in a Sainsbury’s car park, while another reported the chaos it causes near schools. A third individual shared: “It has misread signs, interpreting ten as 70, 19 as 90, and 30 as 80. It’s incredibly dangerous.”

Although drivers can disregard incorrect alerts, some assistance systems integrate TSR with adaptive cruise control, potentially causing the vehicle to autonomously speed up or slow down based on a misread sign.

This poses a significant risk, especially in high-performance vehicles like the £96,000 Porsche Macan Turbo, which can accelerate from 0 to 60mph in just 3.3 seconds.

One Porsche Macan owner called Helen posted online: ‘The speed sign recognition has never worked effectively (or safely) since having the car so I’ve had to turn the function off.

‘After the last time I tried it, the car abruptly changed from 70mph to 5mph when it incorrectly read a 50mph sign. Thankfully nothing fast or heavy was behind me and I could quickly take over driving.’

The £55,000 Mazda CX-60 includes technology that reads speed limit signs and alerts the driver to speed up or slow down, but owners say it is making mistakes

Volvo XC40 owners have complained that the Traffic Sign Recognition system is making potentially dangerous errors

The £96,000 Porsche Macan Turbo, which can go from 0-60mph in 3.3 seconds, can automatically speed up and slow down to match the speed limit

Mazda CX-60 owner Richard Wright, 45, from Tunbridge Wells, Kent, told the Mail: ‘The car has a heads-up display, so all the useful driver information is projected onto the windscreen in front of you, including the speed limit. This is designed to stop you having to look down at your regular dials.

‘When it’s constantly flashing up warnings that you should be doing 80mph in a 30mph, or to slow down to 5mph in a 50mph zone, it’s extremely distracting.

‘On a few occasions, it has caused me to hit the brakes when I was driving perfectly safely and within the law. It is a real issue.’

In other car forums, Fallyn Kinsella posted: ‘Mine always does it in certain areas, mainly where the road drops to 20mph around school zones – plays mayhem with the signs.’

Stephen Gauld reported seeing ‘80 showing while in Sainsbury’s car park’, Chloe Byrne complained about being advised she could do 80mph in a 60mph zone, while Liz Robinson wrote: ‘Ours does that quite often in a 30 area.’

One person described almost daily issues, with ‘speed limits being shown as 5mph, 80mph or 100mph – on roads that were actually 30, 40, 50mph.’

The issue appears to have been ongoing to more than a year, with dealers apparently continuing to sell the vehicles without informing customers of the problem.

Driver assistance technology uses a mix of cameras and GPS data to read speed limit signs and display them on the dashboard. The system is supposed to help motorists stay safe by always showing the legal speed.

But the tech has proved unreliable, mistakenly reading stickers on trucks or even signs on side roads. Volkswagen has recently decided not to install it in cars in Australia, saying the feature was ‘rushed to market’ by competitors and prone to ‘errors’.

Last night, Mazda UK said it is investigating the issue after being contacted by the Mail.

A spokesman said: ‘The safety systems equipped to vehicles are additional aids for the driver, but it is the responsibility of the driver to monitor road conditions, speed and road signs while in control of the vehicle. We are currently investigating the issue raised and will report to our colleagues at Mazda Motor Corporation.’

Porsche said it was working on a fix, but that dirty or unclear traffic signs can throw off the system.

A spokesman said: ‘Owners of the Porsche Macan will soon be offered a new software package, to be installed free of charge at Porsche Centres. This integrates current system improvements and further optimises the driving experience.

‘Among other features, this will introduce further developments to the traffic sign recognition technology. The driver must still pay attention at all times and intervene in cases of doubt. Furthermore, the adaptive cruise control feature on the Macan is an option, and the customer can turn it off.’

Volvo was contacted.