Merged thread: Automatic Emergency Braking activating for no reason

The AEB has always been on on mine, until this evening, it’s now getting turned off with the LKA on every journey.

The AEB has went off twice with me in 3400 miles, and both time have been within a week of each other.

Last week, about quarter past midnight after back shift. M8 motorway, 40mph average speed cameras due to roadworks. No cars for at least a quarter mile ahead or behind me, cruise control set to 40 for the last mile, and all of a sudden, bang, brakes are slammed on hard out of nowhere, absolutely no reason and scared the hell out of me.

2nd time was this evening, sitting 2nd in queue at a red light, single carriage way. I was turning right, indicator on. Lights go green, first car goes straight on, I pull up slowly to the middle of the junction, slightly to the right, again, wallop! Brakes on hard to a stop. Was only doing maybe 4-5mph, didn’t stop me or the guy in the car behind me getting a scare. There was traffic coming the opposite direction on the carriage way, but nothing that should have kicked the AEB in.

To add insult to injury, I washed the car this evening and found more stone chips, this paint is crap! And I took the covers off the alloys to clean them and all my spokes have the “Z” scratch marks on them from the covers. Its booked in for the middle of the month to get the passenger door handle replace due to the button failing, so I’ll have a moan at the service guys while I’m in.

I’m just gonna live with it till it’s pcp is up, but I’ll not be buying another MG after this one. Sorry to say, I wish I kept the Megane or Mini order I had cancelled for this!
 
The MG4 is not the only EV to have this phantom braking issue, Teslas are renown for it with their auto pilot.
The annoying part is you have to turn off these so called 'safety features' at every restart apparently as you cannot permanently disable them after the latest update?

In saying that I have AEB by default on my current ICE car and whilst it has given me an orange flashing light and audible warnings on a few occasions they were legitimate and it has never caused the brakes to slam on.
 
I had a similar issue with the emergency braking coming on while i had the automatic cruise control on. ( I have a 2022 ZS EV with 320km range)
Initially I discussed it with the dealer I purchased th vehicle from
They gave me a load of BS, and basically said it was driver error.
I then contacted the New Zealand importer, told them it wasnt good enough
They readily agreed to an in warranty check ( at the dealership where I purchased the vehicle from)
End result was: radar was mis aligned, plus they did two software updates ( not sure of the detail)
Learning point is, dont take no for an answer , if you think there is something wrong with your vehicle, there probably is.
If you come at it from a safety perspective, they should get invloved in a remedy.
In New Zealand, we also have a Consumer Guarantee Act, amongst other things, the Act says that items must "be fit for purpose.

I had a different issue with a 2018 Kia Sportage, in certain circumstances the auto trans was lumpy. It was a known fault ( but not proactively remedied). A software update fixed the issue
 
My wife was scared sh**less this morning when her MG4 Trophy did a sudden and totally inappropriate emergency stop, whilst travelling at 30mph through a quiet nearby village. A Tesla was following at a safe distance and fortunately no collision took place. The car was then ok to drive away.
There were no nearby pedestrians or obstructions that could have confused to car systems. This has been reported to the dealership (Paul Rigby at Redditch) and I am awaiting a response.
We also have ongoing issues with the infotainment screen going blank or skipping from side to side, the radio and car play intermittently not working and also very unpleasant hypersensitivity of the lane depart functions. The dealer says there are known issues which MG do not have a fix for. Last week I was told that the earliest date the dealer could look at the car was 14/8/23! But if there is no software fix, then what’s the point of taking the car in?
We have also had problems with the charging, which sometimes goes to 100% when set to 80%.
Our confidence in this MG is fading and the dealership has been less than helpful.

The lasted emergency stop issue is downright dangerous. I await a response from the dealer on this, but it may be difficult to persuade my wife to drive it again!
 
There's a very relevant thread on this here.

Emergency braking on level crossing with no nearby cars

Today our MG4 automatically braked on a level crossing with no other vehicles in sight. I was within in the barriers and the car wouldn’t move for what seemed like ages. I have never been so frightened in my life and my heart was pumping. I was debating whether to just run and leave the car on...
www.mgevs.com www.mgevs.com

The bottom line seems to be that some cars rarely if ever do this, and some are distinctly prone to it. Possibly needs something recalibrating, but it's very understandable that drivers lose confidence in the car once it has done this for no apparent reason. (The member whose car did it on the level crossing got rid of the car because his wife's nerves were in tatters.)
 
Having followed the other thread, I think it may be an issue with a camera or other sensor needing to be recalibrated. I hope they can fix this for you.

My car has done it twice, but both times there was a reason. The first time I was driving in traffic along Keighley Main Street, with a row of parked cars on my left. The car suddenly slammed on the brakes with no warning, but because my speed was low I wasn't in any danger of whiplash or anything. What had happened was that a man had come through between two parked cars, stepped out into the road, and opened the driver's door of one of the parked cars, right in front of me. There was in fact enough room for me to pass, if there had been no AEB nothing would have happened, but at least there was a reason for the stop.

The second time was when I was coming up behind a car stopped at road-works. The car obviously thought I wasn't braking in time, and the AEB came on absolutely simultaneously with me braking myself. I only realised what had happened because the force of the braking was harder than I had applied the brake pedal. Again, an obvious reason, and no harm done.

I've also had a beep-beep audible warning a handful of times, usually when I've been coming up behind a parked car and delaying pulling out because of another car coming in the opposite direction, but also at least once when coming up behind a stationary car signalling right. But that's no big deal, the brakes didn't come on.

You were lucky it was a Tesla following you. You were in no danger of being rear-ended. Twitter link to video (hope it works).



The Tesla AEB seems to be the only one that really works. Not that they haven't had their phantom braking problems too; one stopped suddenly in the middle of the new Queensferry Crossing bridge right under the noses of the CCTV cameras, and the clip was still being laughed at on the net weeks later. But Tesla seem to have ironed out the problems.
 
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Deakin said:
Thanks for your response.

There does seem to be a number of clitches in the MG4 which they need to urgently address if the company is to avoid reputational damage.

Graham
Click to expand...
There are a number and they seem to sort them eventually, the locking people in being one.

I genuinely don't believe they give a toss about reputational damage, MG UK customer service is hopeless.
Any customer service that take the stance off "talk to the dealer, it's nothing to do with us, we just sell them the car" tells you all you need to know.
The biggest thing with MG seems to be do your research and find a good dealer.
 
I usually always turn AEB off but don't bother for short journeys. Happened to me a couple of times needlessly. Last time I was only doing about 5-10mph and left me and passenger stunned for a few seconds having been thrown forward in seat belts before realising what happened and then having to quickly manoeuvre car our of way of other traffic to compose ourselves. Only thing that will make MG do anything about is is a big claim for whiplash. All this driver assist stuff is a load of nonsense. If a driver needs it then they shouldn't be driving.
 
Happened to me this morning, overtaking an HGV then the brakes went off. Will speak to the dealership about getting this sorted, IT IS DANGEROUS!!!
 
After having seen that video of all these AEB-equipped cars (except the Tesla) ploughing into cyclists and pedestrians regardless, including the MG4, I'm wondering if it's worth leaving it on. It hasn't gone off with me for no reason, and my feeling was that if it was potentially capable of preventing an accident then I'd leave it on, but if it can't even do that, what's the point?
 
Rolfe said:
After having seen that video of all these AEB-equipped cars (except the Tesla) ploughing into cyclists and pedestrians regardless, including the MG4, I'm wondering if it's worth leaving it on. It hasn't gone off with me for no reason, and my feeling was that if it was potentially capable of preventing an accident then I'd leave it on, but if it can't even do that, what's the point?
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I posted the full NCAP video in response to the cherrypicked one, which showed that the MG4's AEB did work in most of the scenarios tested. Hence why it got the score it did. Of course it's up to the individual whether the frequency and potential danger of false positives outweighs the potential (very rare, but potentially life-saving) benefit of the system activating correctly.
 
I think I missed that link - do you still have it handy? I'd like to see it.

I don't mind leaving it on if there is a possibility that it might prevent a serious injury. So far the two activations I've experienced have been explicable. The number of people reporting unprovoked activation is a bit worrying, but of course when that happens people tend to come here to complain about it, understandably, so it won't be a representative sample.
 
Sure.


I wonder whether these systems have to be re-tested by NCAP if they make any software changes.
 
Thanks very much.

Having watched that, it's quite reassuring. It does work quite a lot of the time. I'll keep mine on unless it starts behaving badly, which it hasn't as yet.
 
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Mine only seems to misbehave when I have ACC active. ?‍♂️ (As in - when I don't have ACC active I can't recall AEB ever operating; I've only noticed it when ACC has been active).
 
On both occasions when mine activated I was not using ACC. But having said that, these were not random events, in both cases there was a reason.
 
Just wanted to share and ask if anyone can offer any advice.

It’s happened twice now since I’ve had the car but this time was more of an issue.
Driving at about 35 when the car slammed on the brakes. No car in front (or behind luckily) but I can only put it down to a pedestrian on the edge of the kerb but I wasn’t near enough to be a reason.

Anyone else experienced this? Are there any ways to minimise the chances it happening again? If someone was behind me too close it would have been a rear end shunt without a doubt
 

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