Merged thread: Automatic Emergency Braking activating for no reason

[Willo]

I have an early MG4 Trophy long range which has now covered 17000 miles, had its first service with lots of updates, and in general terms has been a great ownership experience. I did experience the issue of being locked in the car (3 times) about 2 weeks into my ownership but that was resolved with a software update.

[1] Since the first service some 2000 miles ago I have experienced on 3 occasions now, whilst driving at about 20mph what seems to be an emergency stop for no apparent reason I.e nothing passing behind or in front, luckily no other cars were close enough to cause an accident.

[2] Also since the service and the updates I have had to turn off Lane keeping assist every time I get in the car (tedious and boring) as I find the action of the so called assist violent and irritating. Is there away of turning the dam thing off as I can’t recall it being noticeable before.

Any help with the above would be appreciated.

 

[Surfdog]

All the time. Its been well discussed on previous posts. A couple of months ago my Trophy went in for lka update and I also complained about unwanted emergency stops. Don't know what they did but since then I haven't had any and on a few occasions I get warning beeps if a car in front is too close but no whiplash injuries since then. I think there might be a sensitivity setting they turn down.

 

[Rolfe]

There's a scary thread somewhere from someone who had it happen on a level crossing. I think they got rid of the car because their wife refused to drive it again, or something like that.

 

[Willo]

All the time. Its been well discussed on previous posts. A couple of months ago my Trophy went in for lka update and I also complained about unwanted emergency stops. Don't know what they did but since then I haven't had any and on a few occasions I get warning beeps if a car in front is too close but no whiplash injuries since then. I think there might be a sensitivity setting they turn down.

Thank you that’s great info - I will ask my dealer

 

[MelanieMoxon]

Yes, I was manouvering at a cross roads. I was on the main road turning right accross traffic. A van had been waiting to turn out of the side road on my left (turning right accross me) I could see the road ahead was clear, but behind me there was a short queue. I elected, being polite and all that to let the van go. He set off and once he was all but clear of me (maybe half a meter) I set off with the intent of turning a little bit left and then swinging right.

The car had decided that this was a collision risk and duly applied the brakes bringing me to a rather sharp halt from the 5mph or so I was doing.

It has also done it several times in long 20mph zones where I have been using the cruise control and it has decided that a parked car is a collision risk.

 

[Willo]

Thanks Melanie - that all sounds familiar and in line with what I am experiencing - I am going to check with the dealer on Monday 25th to try and ascertain if as suggested by another reply that the severity of the event can be reduced.

I will post the answers I get - if any ?‍?

 

[Rolfe]

The problem I've had with parked cars and 20 mph zones when I'm using ACC has been unnecessary braking, not emergency braking. The car will slow right down even though there's plenty space ahead, so that I have to accelerate through it. It hasn't actually slammed on the brakes.

 

[Willo]

The problem I've had with parked cars and 20 mph zones when I'm using ACC has been unnecessary braking, not emergency braking. The car will slow right down even though there's plenty space ahead, so that I have to accelerate through it. It hasn't actually slammed on the brakes.

Thanks for this, I haven’t experienced this one - but trust me when the conditions are as explained the brakes go on and nearly break your neck as you aren’t expecting it, very frightening. I have tried turning things off especially alert + AEB to no avail. Then again I don’t really want to get into a car and have to go through a long winded settings session only to have to do it again at the next start. I really think that MG need to get to grips with the idea that drivers should be able to set the vehicle as they want it and save those settings until the driver wants to change them and not the other way around.

 

[Kithmo]

Mine must be unique, am I the only one who's not had it engage, I've had a warning beep a couple of times but it's never actually braked.

 

[AdyC]

Mine went in about 6 weeks ago and had the radar aligned and toned down in the settings along with a software update which pretty much screwed up the informant screen which freezes and goes blank now.
A week ago mine did an emergency stop whilst passing a vehicle parked at the side of the road leaving me in the middle of the carriageway so i again went to the dealer who fortunately is a couple of miles away and its booked in again first week in October. Its also being looked at for the bluetooth issues with my phone and digital key . Hopefully the new update will fix the screen freezing as it was fine before, Its a shame as its such a good car.

 

[Willo]

Mine went in about 6 weeks ago and had the radar aligned and toned down in the settings along with a software update which pretty much screwed up the informant screen which freezes and goes blank now.
A week ago mine did an emergency stop whilst passing a vehicle parked at the side of the road leaving me in the middle of the carriageway so i again went to the dealer who fortunately is a couple of miles away and its booked in again first week in October. Its also being looked at for the bluetooth issues with my phone and digital key . Hopefully the new update will fix the screen freezing as it was fine before, Its a shame as its such a good car.

Like you say a great car spoiled - although I didn’t have this issue before the service and updates.

 

[robert9962]

It happened to me for the first time the other day. Luckily I wasn't going fast and nobody behind me.

It's dangerous, hopefully when I take the car for its first service an update will stop it happening again!

 

[AdyC]

Ill let the dealer look at mine again and if no joy ill contact the DVSA. I totally agree, dangerous and scary when it goes off as its so aggressive.

 

[mg4mc]

AFAIK, the radar "alignment" process is just self learning! They drive it along a straight road (which apparently needs regular posts or obstacles either side - good luck finding that road) and stay within a specified speed range then give it back to you.

 

[Kithmo]

AFAIK, the radar "alignment" process is just self learning! They drive it along a straight road (which apparently needs regular posts or obstacles either side - good luck finding that road) and stay within a specified speed range then give it back to you.

I think this is where they did mine.

 

[SimonS]

Mine must be unique, am I the only one who's not had it engage, I've had a warning beep a couple of times but it's never actually braked.

Same here. I have had it go off in the past in a Mini, 2 different Skoda's and 3 BMW's. There is a spot in the long stay carpark at Edinburgh airport where I could trip it every time. There was one of those large square rubber road speed pillows positioned just on the top of a slight rise and the system would see it as a wall. I stopped using that bit of the carpark.

This is not unique to MG.

 

[MelanieMoxon]

I had another good one yesterday, not an emergency brake application but the ACC bringing the car to a near hault before I clicked it off and continued.

I was driving down a 30mph zone, very little traffic and quite long, hence the cruise usage. The road widended out allowing parking on both sides but still having full width lanes. The car obviously saw the parked cars on my left and assumed a traffic queue and decided to stop the car. I let it do its thing as there was nothing behind me. It was quite disconcerting on a wide road, I'd have of understood if I had gotten too close to a parked car but the distances involved were considerable.

My GF looked at me wondering what the hell I was playing at, I just laughed and explained the car did it by its self.

 

[Kithmo]

I had another good one yesterday, not an emergency brake application but the ACC bringing the car to a near hault before I clicked it off and continued.

I was driving down a 30mph zone, very little traffic and quite long, hence the cruise usage. The road widended out allowing parking on both sides but still having full width lanes. The car obviously saw the parked cars on my left and assumed a traffic queue and decided to stop the car. I let it do its thing as there was nothing behind me. It was quite disconcerting on a wide road, I'd have of understood if I had gotten too close to a parked car but the distances involved were considerable.

My GF looked at me wondering what the hell I was playing at, I just laughed and explained the car did it by its self.

A quick flick of the right indicator, as you approached the parked cars, would have prevented this.

And this is where they calibrated it to the edge of the road.

 

[tonybridge]

Mine must be unique, am I the only one who's not had it engage, I've had a warning beep a couple of times but it's never actually braked.

Not unique, as neither have I. The LKA, even on the default, is very mild - the only issue I have with that is that it seems completely random, I can drive over miles of white lines, and it will not complain, then suddenly twitch with no lines at all... huh? But it's no big deal.

I've not had any sudden braking...

 

[Kithmo]

Not unique, as neither have I. The LKA, even on the default, is very mild - the only issue I have with that is that it seems completely random, I can drive over miles of white lines, and it will not complain, then suddenly twitch with no lines at all... huh? But it's no big deal.

I've not had any sudden braking...

I thought LKA was a bit random at first until I found out it's speed related.
It turns off under 35mph and comes back on at 35mph and above.