MG issues software update following Which? safety concerns with MG4
In 2024, our lab tested the MG4 electric car and highlighted serious issues with the car’s lane-departure warning and lane-keep assistance technology.
After publishing our findings, we heard from more than 100 MG4 owners who told us about concerns with their MG4 cars.
Since then, MG has worked together with the Vehicle Certification Agency (VCA) – an agency of the Department for Transport that approves all vehicles for sale in the UK – to develop and roll out a software update for MG4 cars.
Read on to find out what the problem was, MG's update and what MG4 owners need to do now.
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What was the problem with the MG4?
When testing an MG4 last year, our lab testers noticed unusual behaviour with its lane-departure warning and lane-keep assistance systems.
On one occasion, when the tester drove on a narrow country road and had to pass another car coming the other way, the MG4’s lane-keep assistance steered away from the nearside edge of the road and towards the centre – and the oncoming car.
On a wider road with a clearly defined centre line, the lane-keep technology then twice decided that the car had left its intended lane and pulled it onto the wrong side of the road.
We asked MG4 owners whether their experiences reflected ours. Most said the car’s lane assistance and lane-departure warning technologies had caused them problems when driving.
We also heard from many owners of other cars, who told us about their experiences with lane-keep assist – suggesting there’s plenty of disquiet with the technology in general.
What's the situation now?
Since we initially reported on the problem in July 2024, we’ve contacted MG numerous times to better understand the issue and what MG was going to do about it.
To get a fuller understanding of the situation, we’ve also spoken to organisations including Euro NCAP, Thatcham Research and the VCA.
In January 2025, the VCA told us: ‘The Vehicle Certification Agency can confirm that we have been working with the manufacturer to approve an update to the MG4 Advanced Driver Assistance System (ADAS), which accounts for behaviours identified by the Which? investigation … our specialist team will work with the manufacturer to oversee the release of the updated software to vehicles in the UK.'
On 6 February 2025, an MG spokesperson told us: ‘We can confirm that MG Motor UK has recently issued an update to the relevant MG4 EV software, which our national dealer network will implement during any scheduled maintenance or servicing work.’
We asked MG whether MG4 owners could get the update installed ahead of their next scheduled service, but as yet haven't had a response.
If you’re concerned about the behaviour of your MG4 or have questions about the update, we recommend you contact your local MG dealership.
If you've had the update, we'd like to hear from you (scroll down for details).
What is lane-keep assist?
The technology goes by various names depending on manufacturer, but in general lane-keep assist is designed to keep your car in the intended lane.
Precisely how it does this depends on the car in question and the settings chosen by the driver. Most cars use a combination of audible alerts to warn when the car is drifting out of lane, along with a small amount of automated steering to guide it back into the intended lane (the force of these steering adjustments also varies depending on the car).
Lane-keep assist has been mandatory on all new cars sold in the UK since 2022 and is also available on many older models.
What is the MG4?
MG has its roots in the UK from the 1930s, but today it’s a Chinese-owned brand that specialises in family cars, including full-electric vehicles such as the MG4.
Launched in 2022, the MG4 is a popular five-door medium-sized hatchback, not least because of its relatively low price compared with other electric cars. It was also the fourth-bestselling electric car in 2024, according to data from industry body the Society of Motor Manufacturers and Traders (SMMT).
Read our full review of the MG4.
We want to hear from you
We’re keen to hear from MG4 owners to find out how the update process was and what impact it's had.
We’d also like to hear from drivers of other cars about their opinions and experiences of lane-assist technology.
Send your comments to helpwanted@which.co.uk.
