Merged thread: Automatic Emergency Braking activating for no reason

[salty]

Yeah ... i have a colleague who leases a mercedes and i have heard him making remarks a few times that the LKA bothered him and he would be happier without it. For such an expensive car that is telling.

Agree. As bad as the LKA is in some MGs.
It's by no means exclusive to MGs.
Far more expensive motors, suffer from it too. Although I know that doesn't particularly help MG owners.

 

[GulaebakavaliUK]

Hi all — I’m a UK-based MG4 SE (2022) owner. For over a year we experienced repeated AEB phantom braking — sudden, hard stops with no obstacle. Despite multiple dealer visits, nothing was fixed. I wrote to MG UK but received no meaningful action.

In late June 2025, the car braked violently for no reason and we were rear-ended by the car behind. Thankfully, my wife and I avoided serious injury, but my MG4 was damaged and the other car was a write-off.

Insurance waived my excess (not my fault) and covered repairs, but we now have a phobia of driving this car — we turn off AEB just to feel safe but we have to do that every journey. Even so, the fear remains. The car’s value has also collapsed — from over £26,000 to under £10,000 in less than 3 years, largely due to safety concerns in our view.

I’m asking fellow owners:

• Have you experienced phantom braking or had to turn AEB off? Does it still brake after that?
  
  
• If reported to a dealer, what was their response? Were there software updates or hardware changes?
  
  
• Has anyone reported this to the DVSA? (More reports help trigger a formal safety investigation.)
  

Looking at these discussion there seem many similar reports from UK MG4 drivers of sudden, inappropriate braking and near-misses. Even a friend with an MG4 Trophy has had the same issues.

 

[GulaebakavaliUK]

I agree Les, I really do. It is the way things are heading sadly.

Completely agree, i already had an accident in Mg4.

 

[Tuareg]

I've had zero AEB interventions and it's enabled all of the time.

 

[salty]

Hi all — I’m a UK-based MG4 SE (2022) owner. For over a year we experienced repeated AEB phantom braking — sudden, hard stops with no obstacle. Despite multiple dealer visits, nothing was fixed. I wrote to MG UK but received no meaningful action.

In late June 2025, the car braked violently for no reason and we were rear-ended by the car behind. Thankfully, my wife and I avoided serious injury, but my MG4 was damaged and the other car was a write-off.

Insurance waived my excess (not my fault) and covered repairs, but we now have a phobia of driving this car — we turn off AEB just to feel safe but we have to do that every journey. Even so, the fear remains. The car’s value has also collapsed — from over £26,000 to under £10,000 in less than 3 years, largely due to safety concerns in our view.

I’m asking fellow owners:

• Have you experienced phantom braking or had to turn AEB off? Does it still brake after that?
  
  
• If reported to a dealer, what was their response? Were there software updates or hardware changes?
  
  
• Has anyone reported this to the DVSA? (More reports help trigger a formal safety investigation.)

Looking at these discussion there seem many similar reports from UK MG4 drivers of sudden, inappropriate braking and near-misses. Even a friend with an MG4 Trophy has had the same issues.

To the forum.

 

[Martinonline]

@GulaebakavaliUK, I have not had any phantom brakings in my Trophy since 2023. After the first couple I lowered the FCA sensitivity to Medium. (It can go to Low and it is kept at level until changed.)

After the second service with SC077 I find I can revert to high with no ill effect.

 

[OriginalBigAl]

Since the second day of ownership mine as been permanently disabled. Wednesday this week I was on a downhill sweeping left hand bend with restricted vision . An oncoming Nissan ( uphill right hand curve also blind beyond 50m ) decided to overtake a cyclist giving him 3m of clearance. This put him with 3/4 of his car in my lane . The closing speed was around 160 km/h with around 40m of distance between us . I managed to heavy brake and dive for the remaining bit of what was left of my lane. I do not know what the reaction of the other driver was but the door mirrors just missed each other and the outside wheels were just scraping the verges .
I have no idea if the Nissan had AEB but I would guess that if mine had been active it might have cut in after I had released the brakes to regain better steering input . In that case it possibly could have sent me off the road to the right but it would not have been able to stop the car in what distance was left , and would have interfered with what ever decisions I had made. Off it stays!
Any way no injuries or damage unless you count the sudden onset of my wife's sore throat. Such loud language and screeching.!

 

[Tuareg]

... or if the other guy was half a metre even further acrosss the road, AEB might have even saved your life...

 

[NLMGSAN]

Since the second day of ownership mine as been permanently disabled. Wednesday this week I was on a downhill sweeping left hand bend with restricted vision . An oncoming Nissan ( uphill right hand curve also blind beyond 50m ) decided to overtake a cyclist giving him 3m of clearance. This put him with 3/4 of his car in my lane . The closing speed was around 160 km/h with around 40m of distance between us . I managed to heavy brake and dive for the remaining bit of what was left of my lane. I do not know what the reaction of the other driver was but the door mirrors just missed each other and the outside wheels were just scraping the verges .
I have no idea if the Nissan had AEB but I would guess that if mine had been active it might have cut in after I had released the brakes to regain better steering input . In that case it possibly could have sent me off the road to the right but it would not have been able to stop the car in what distance was left , and would have interfered with what ever decisions I had made. Off it stays!
Any way no injuries or damage unless you count the sudden onset of my wife's sore throat. Such loud language and screeching.!

160 km/h?
ABS should have allowed you to control the steering. Did you expect that this was insufficient?
Btw, good to hear you are both alive and kicking.

 

[tsedge]

In late June 2025, the car braked violently for no reason and we were rear-ended by the car behind. Thankfully, my wife and I avoided serious injury, but my MG4 was damaged and the other car was a write-off.

So sorry to hear this, glad you weren't seriously hurt. It was only a matter of time before this happened.

• Have you experienced phantom braking or had to turn AEB off? Does it still brake after that?

Yes and yes. If you switch it to "Alert" mode then it doesn't (and can't) use the brake but it can still warn you if it triggers. This is what I typically do.

• If reported to a dealer, what was their response? Were there software updates or hardware changes?

Various software updates to car modules, they tried several times and they made it behave much better. I went for nearly a year without getting a problem, but for some reason it came back recently (it is always set to "Low" sensitivity).

• Has anyone reported this to the DVSA? (More reports help trigger a formal safety investigation.)

I have not. It is quite rare and I am satisfied I can just turn it off.

My experience with other makes (ie non MG) is similar, which is unsurprising as there are a few common manufacturers that make these systems. MG seem to have done a poor job of integrating it initially and mostly fixed it with later updates.

It is impossible to know if you have the right software updates, generally we have to rely on having a competent dealer who checks and applies any needed - but this will typically only happen if you complain and ask it to be fixed under warranty as that's the only way the dealer is paid by MG to apply any needed update.

Looking at these discussion there seem many similar reports from UK MG4 drivers of sudden, inappropriate braking and near-misses. Even a friend with an MG4 Trophy has had the same issues.

Yes, it is fairly common, especially if the vehicle hasn't had the latest updates, which many older cars haven't.

 

[OriginalBigAl]

... or if the other guy was half a metre even further acrosss the road, AEB might have even saved your life...

We have one present, one past, and a multitude of hypothetical futures. ?

 

[OriginalBigAl]

160 km/h?
ABS should have allowed you to control the steering. Did you expect that this was insufficient?
Btw, good to hear you are both alive and kicking.

I was doing 90 kmph the other at least 70 kmph, from my biking training , before AEB on bikes , I was told don't look at the danger, find an escape route and go for it. If braking is the best option , use it, if manoeuvrability use that. Even without the cars input of AEB ( which by all accounts should not have kicked in, I was braking ) having the braking forces on the front wheels reduces the steering accuracy which in that situation I found less preferable . There was no way I was going to stop in the quickly reducing distance , with or without assistance so letting off the brakes with around 10m gap and going for the escape route was my choice. If in that short window had AEB engaged , well that's up for debate? but ultimately hypothetical .

 

[NLMGSAN]

ABS works very fine on the MG. Last winter on one of the few days a sharp overnight frost created a very icy 60kmh road. I had to brake suddenly an maximally because some dude coming from the right missed the stop sign. Distance about 25 mtrs? Wheels never locked up preventing me from steering. If I would not have steered the car to the right so I could go Behind and around him, I would have smashed his car somewhere between the left rear door and the rear lights (it was a Saab). I escaped, he did a 180...
I parked the car in the frozen mud and grass to see if he was ok. Adrenaline pooring out of my hair....
He got out of the car, looking terrified. Then he walked away from his car, which was facing straight to the oncoming traffic in his lane. Unfortunately, a Ford Focus locked his wheels on the icy road and both cars kissed heavily.

If you have experienced these completely unnecessary braking issues I fully understand you wish to avoid it. What I understood was that AEB is triggered by the front collision system or even ACC (like on a bendy road). Question is: should we disable AEB? Or the system that triggers it?

 

[chromeskull]

This has triggered my AEB 3 times when slowing to turn right. Really annoying as it happens just as I start to turn the wheel. I then have to sit like a plank for 5 seconds until it lets me continue (seriously locks it up).

 

[salty]

Perhaps it prefers Maccies.

 

[OriginalBigAl]

AEB ........ anti extra bovine ........ snacks. Its part of the new Euro NCAP regulations as a counterpoint to the Orange Idiot.

 

[Ian Key]

This has triggered my AEB 3 times when slowing to turn right. Really annoying as it happens just as I start to turn the wheel. I then have to sit like a plank for 5 seconds until it lets me continue (seriously locks it up).View attachment 38905

I guess the car thinks the bollard is a child. Try just applying the brakes gently so the car knows you've seen it.

 

[Martinonline]

Did the braking occur when there were cars approaching you from the bend?

 

[gary333]

This has triggered my AEB 3 times when slowing to turn right. Really annoying as it happens just as I start to turn the wheel. I then have to sit like a plank for 5 seconds until it lets me continue (seriously locks it up).View attachment 38905

It's protesting. It doesn't want to be in Worksop