MG4 Trophy LR: spontaneously engaged Reverse

GadjoDave

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Location
Llanelli, UK
Driving
MG4 Trophy LR
6 month old MG4 Trophy LR, bought new.

It's my first EV, and I'm generally delighted with it, apart from some minor annoyances which have already been discussed at length on this forum: default activation of LKA, poor headlight adjustment with a dark band between dipped and main beams, and badly written buggy firmware and accompanying iphone app which should and could easily be fixed by MG releasing software updates.

I've read other threads re: False positive activation of AEB and LKA, and Selector failure when trying to go into reverse; but I experienced a new problem three weeks ago which I though I should inform the community about, and wonder if anyone has had a similar experience or can offer an explanation.

10 am, weather fine. Queuing at traffic lights on a level road. Both hands on the wheel. Central selector in "F" mode. I held the car on the foot brake for 15s, then as the queue moved forward, I took my foot off the brake and pressed the accelerator to pull away. However instead of accelerating forwards, the selector spontaneously flicked from "F" to "R" and the car accelerated backwards. It would have hit the car behind me, but fortunately the rear AEB deployed and I was brought to a sudden halt, leaving myself and the driver behind me somewhat shaken.

3h later, driving home, despite turning off all of the default automated AEB and LKA features before setting off, the dash suddenly indicated that these features had become active again, and a few minutes later driving on an open road at 30 mpH, AEB spontaneously deployed bringing the car to a sudden halt. Fortunately no other road users were in the vicinity and no harm resulted.

I informed my local dealership, who were unable to explain the problem. They contacted MG head office, who advised "Don't worry: it was just a glitch".
I explained to my local dealer that I was not happy with this response, and that I would not drive the car until the problem was properly diagnosed and fixed, as a repeat incident could result in a serious accident for which I would be liable.

MG reluctantly agreed to take the car in for diagnostics, and asked for dashcam footage of the incident.
My Garmin Mini 2 dashcam is powered via a USB adapter in the central cigarette lighter socket.
Footage of all activity before and after these incidents was captured on the dashcam's SD card; but interestingly there were gaps in the footage precisely at the time that both incidents occurred, suggesting that these incidents may have been associated with a power outage to the cigarette lighter socket and perhaps also to other areas of the car.

The dealership has upgraded some software, changed collision sensor sensitivities, and are currently replacing the central selector unit.
Meanwhile they've kindly provided me with an MG5 courtesy car, so I'm staying mobile and all-electric.

I'd be interested in the community's possible explanations and advice. Many thanks in anticipation.
 
6 month old MG4 Trophy LR, bought new.

It's my first EV, and I'm generally delighted with it, apart from some minor annoyances which have already been discussed at length on this forum: default activation of LKA, poor headlight adjustment with a dark band between dipped and main beams, and badly written buggy firmware and accompanying iphone app which should and could easily be fixed by MG releasing software updates.

I've read other threads re: False positive activation of AEB and LKA, and Selector failure when trying to go into reverse; but I experienced a new problem three weeks ago which I though I should inform the community about, and wonder if anyone has had a similar experience or can offer an explanation.

10 am, weather fine. Queuing at traffic lights on a level road. Both hands on the wheel. Central selector in "F" mode. I held the car on the foot brake for 15s, then as the queue moved forward, I took my foot off the brake and pressed the accelerator to pull away. However instead of accelerating forwards, the selector spontaneously flicked from "F" to "R" and the car accelerated backwards. It would have hit the car behind me, but fortunately the rear AEB deployed and I was brought to a sudden halt, leaving myself and the driver behind me somewhat shaken.

3h later, driving home, despite turning off all of the default automated AEB and LKA features before setting off, the dash suddenly indicated that these features had become active again, and a few minutes later driving on an open road at 30 mpH, AEB spontaneously deployed bringing the car to a sudden halt. Fortunately no other road users were in the vicinity and no harm resulted.

I informed my local dealership, who were unable to explain the problem. They contacted MG head office, who advised "Don't worry: it was just a glitch".
I explained to my local dealer that I was not happy with this response, and that I would not drive the car until the problem was properly diagnosed and fixed, as a repeat incident could result in a serious accident for which I would be liable.

MG reluctantly agreed to take the car in for diagnostics, and asked for dashcam footage of the incident.
My Garmin Mini 2 dashcam is powered via a USB adapter in the central cigarette lighter socket.
Footage of all activity before and after these incidents was captured on the dashcam's SD card; but interestingly there were gaps in the footage precisely at the time that both incidents occurred, suggesting that these incidents may have been associated with a power outage to the cigarette lighter socket and perhaps also to other areas of the car.

The dealership has upgraded some software, changed collision sensor sensitivities, and are currently replacing the central selector unit.
Meanwhile they've kindly provided me with an MG5 courtesy car, so I'm staying mobile and all-electric.

I'd be interested in the community's possible explanations and advice. Many thanks in anticipation.
Sorry to hear about the issue with your Trophy LR. I have the same car, and having parked up and put it into P (with confirmation from the red backlight) I opened the door, stepped out, and just as I was about to close the door the damn thing started up and drove itself into a lampost). I reported it immediately to my supplying dealer only to receive a series of shrugged shoulders and, "Oh, well that shouldn't happen". I even have the dashcam footage to prove it, so now I have a habit of pressing the selector knob for Park AND lifting the electronic handbrake button, and then waiting for both red backlights to come on. Even then, I open the door and wait a few moments with my foot covering the brake. Apparently, this was not an uncommon event on some of the VW e-Golf's.
 
6 month old MG4 Trophy LR, bought new.

It's my first EV, and I'm generally delighted with it, apart from some minor annoyances which have already been discussed at length on this forum: default activation of LKA, poor headlight adjustment with a dark band between dipped and main beams, and badly written buggy firmware and accompanying iphone app which should and could easily be fixed by MG releasing software updates.

I've read other threads re: False positive activation of AEB and LKA, and Selector failure when trying to go into reverse; but I experienced a new problem three weeks ago which I though I should inform the community about, and wonder if anyone has had a similar experience or can offer an explanation.

10 am, weather fine. Queuing at traffic lights on a level road. Both hands on the wheel. Central selector in "F" mode. I held the car on the foot brake for 15s, then as the queue moved forward, I took my foot off the brake and pressed the accelerator to pull away. However instead of accelerating forwards, the selector spontaneously flicked from "F" to "R" and the car accelerated backwards. It would have hit the car behind me, but fortunately the rear AEB deployed and I was brought to a sudden halt, leaving myself and the driver behind me somewhat shaken.

3h later, driving home, despite turning off all of the default automated AEB and LKA features before setting off, the dash suddenly indicated that these features had become active again, and a few minutes later driving on an open road at 30 mpH, AEB spontaneously deployed bringing the car to a sudden halt. Fortunately no other road users were in the vicinity and no harm resulted.

I informed my local dealership, who were unable to explain the problem. They contacted MG head office, who advised "Don't worry: it was just a glitch".
I explained to my local dealer that I was not happy with this response, and that I would not drive the car until the problem was properly diagnosed and fixed, as a repeat incident could result in a serious accident for which I would be liable.

MG reluctantly agreed to take the car in for diagnostics, and asked for dashcam footage of the incident.
My Garmin Mini 2 dashcam is powered via a USB adapter in the central cigarette lighter socket.
Footage of all activity before and after these incidents was captured on the dashcam's SD card; but interestingly there were gaps in the footage precisely at the time that both incidents occurred, suggesting that these incidents may have been associated with a power outage to the cigarette lighter socket and perhaps also to other areas of the car.

The dealership has upgraded some software, changed collision sensor sensitivities, and are currently replacing the central selector unit.
Meanwhile they've kindly provided me with an MG5 courtesy car, so I'm staying mobile and all-electric.

I'd be interested in the community's possible explanations and advice. Many thanks in anticipation.
What's "F" mode??
 
This happened to someone in Australia. I am not sure if it is on this site or the Australian MG facebook forum. It happened at some traffic lights & the car just took off in reverse. Luckily there was no-one behind.

The selector was in "D" which now stands for "Dunno' what way to go. Also "R" stands for "Racing" which is what happened backwards. I assume "N" stands for "Not Sure" what I want to do.:D
 
I never had the reverse engage randomly...

However - it happened to me quite a few times that I press/slap the P button, I get the tactile feedback but Park isn't engaged (and the car starts forward after I take my foot off the brake).

Now I tend to press the button and I visually check that it lights up before taking the foot off the brake (and it makes me appreciate the sturdy lever from my RAV4 PHEV even more - there is no doubt what you've selected with that).

Just one more niggle to the growing list...

Since my dealer told me that the under tray bulge is there "by design" I'd expect them to say that this is "not a bug, it is a feature" (so I haven't even bothered to mentioned it).
 
Did you put it in "F" mode when you stopped (P) or did you pull up in "F" mode (D) ? ?
ISTR someone having this occur when using OPD.
Mine doesn't have OPD and I prefer the car to creep when I let go of the brake anyway, in this situation you'd have experienced the car creeping backwards before pressing the accelerator pedal if not using OPD.
 
Did you put it in "F" mode when you stopped (P) or did you pull up in "F" mode (D) ? ?
ISTR someone having this occur when using OPD.
Mine doesn't have OPD and I prefer the car to creep when I let go of the brake anyway, in this situation you'd have experienced the car creeping backwards before pressing the accelerator pedal if not using OPD.
Hi. Thanks for your reply and question. In my case, I wasn't aware that One Pedal Drive (OPD) mode was engaged at any point: I was using the default start-up settings for regular driving, and this was confirmed by the dashboard display. I'd stopped in traffic with the selector in the "D" position and my foot on the brake. Both hands were on the steering wheel throughout: I didn't touch the selector control at any point, so didn't apply "P" mode; and I didn't use the equivalent of the "handbrake" (the switch to the rear of the selector) to hold the car. There was no incline on the road. When the traffic moved off, I lifted my foot from the brake and pressed on the accelerator. The car accelerated (rather than crept or rolled) backwards. The AEB deployed before I hit the car behind me. Then I looked down at the selector control and saw that it had shifted itself from the "D" position to the "R" position. Hope this additional detail is helpful. Thanks again
 
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My suspicion is that something caused the 12V battery voltage to collapse. Perhaps one or two cells of the 12V battery shorted briefly. It sounds unlikely as I type this. But it would explain the lack of dash cam co average of the incident.

Perhaps the DC-DC stopped working and the 12V battery just ran flat. But then it would have to have recovered and charged the battery enough to continue driving after the incident. Also sounds unlikely.
 
Thanks everyone for your helpful comments and suggestions. My local dealership contacted me today to ask me to pick up the car: apparently MG's Head Office have remotely upgraded the software for the Gateway, BCM, and Selector. Head Office have said that there is no need to physically exchange the Selector for a new one, and that the problem has now been fixed and will not happen again. I'm still none the wiser why this happened in the first place, and therefore not convinced that it couldn't happen again. The local service manager told me that they have no idea either: "It's all about the software now: the most useful tool you can have is a ring spanner to disconnect and reconnect the battery, which generally solves problems in the same way that you'd power down and restart your home computer". Maybe, but this isn't really an acceptable solution for safety-critical software problems: home computer crashes don't kill people; whereas car crashes do. It seems there's nothing else I can do. At least it has been documented that MG have been made aware of the problem and have signed it off as fixed and safe to drive, so if it does happen again and it causes an accident, then I would hope that MG rather than myself would be liable.
 
MG head office didn't remotely connect - the dealer technician connected a laptop to the car and then they remotely connected to MG's server to download the latest software updates that had been assigned to your car's VIN.

The end result was the same - just the process as explained to you was incorrect. :)
 

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